I could say I "nearly" perfected my design for this build. I won't say it's unique, but it's definitely an interesting one. I'll go into details about my build, possible alternatives, abandoned ideas, and flaws.
https://preview.redd.it/im2z4tuaszoa1.png?width=629&format=png&auto=webp&s=4f419235283d9c9ee01eb3a2f3aa250f22de5a5c
As for the build itself, I'm currently sitting on:

• Dual Reduvia daggers +10
• A buckler for parrying
• Either Varre's Bouquet or a life stealing claw special
• White Mask (with medium weighted armor)
• Lord of Blood's Exultation, Taker's Cameo, Godskin Swaddling Cloth, and the Rotten Winged Sword Insignia (no, I didn't stack it with Millicent's Prosthesis because I'm not a jerk).
• Update: Dragon Communion Seal for casting "Flame, Grant me Strength" and "Golden Vow".
• Flask of Wondrous Physick: Thorny Cracked Tear and Crimsonwhorl Bubbletear

https://preview.redd.it/fkusqaxbszoa1.png?width=1036&format=png&auto=webp&s=6359966bc325499da8674970b17683f0a2d67f0f
The damage of this build is crazy. Aside the DEX/ARC scaling, the massive bleed proc damage is an obvious boost. After the bleeding effect is applied, I gain a temporary 30% total increase in damage output (30 seconds for the exultation, and 20 seconds from the mask). With rapid strikes applied, I can gain up to another 13% damage increase if I'm fast enough with the sword insignia. On top of that, with the thorny cracked tear applied from the physick, that's another possible 20% increase in damage (with rapid attacks).
In total, I'm getting a temporary total boost of up to 63% of added damage per rapid strike (with bleed procs). With Golden Vow and Flame, Give Me Strength, that total is increased to 98%. The biggest downside is that since I'm using daggers, I have to be VERY close to enemies. In addition, my poise isn't the highest, which means I'll be getting bounced around like a pinball on tournament day (unless I am able to parry enemies often, which I'm able to do on various occasions).
As for the healing portion, that lies with Rykard's Greatrune, Taker's Cameo, and the Godskin Swaddling cloth. Rapid strikes can heal me slightly, but killing enemies outside of boss rooms essentially makes the flasks nearly obsolete. If I need even more health, I can either perform the life stealing special attacks from Varre's Bouquet or the Life steal grab with a claw (which is riskier, but also more rewarding).
https://preview.redd.it/o92io6wcszoa1.png?width=200&format=png&auto=webp&s=c7c677c46b0c6388335f9dc30996c10198b2cd6e
Possible alternatives that didn't really pan out:

• I attempted to use the Venomous Fang with bleed and poison buildup so that I can have a 50% applied damage boost via the White Hood and Lord of Blood/Kindred of Rot exultation talismans. While the desired effects were good, I felt the claws were too slow and slightly weaker to build up enough damage compared to the faster Reduvia daggers. Granted, the claws hit harder and staggered enemies, but I felt the damage wasn't good enough and wouldn't work well with the sword insignia talisman/Thorny cracked tear physick.

https://preview.redd.it/5peqkm4eszoa1.png?width=200&format=png&auto=webp&s=47bed54e814a7d646ffb519e3c5ddad5ee7c4830

• I originally proc'd bleed and poison with dual great knives. While they still had the speed, they didn't have the damage or the proper bleed proc. Poison was easily applied, but the Kindred of Rot talisman only offers this boost for 20 seconds instead of 30 seconds like the Blood exultation.
• I had considered dual wielding the Scorpion Stingers for rot damage boosts with the applied Exultation. However, if I wanted a similar 30% increase with the white hood, I would have to equip the "Mushroom Crown". I don't find that head piece aesthetically pleasing. Plus, bleed proc can deal much more damage in the long run.

Future plans:
I've been going through NG+ slowly with friends. I have yet to try out "Malenia's Greatrune" (haven't fought Malenia again, but I will eventually). While I still adore Rykard's Greatrune, I want to experiment with Malenia's "Bloodborne-esque" ability. Since I'm a bit of a reckless rapid-poker, I feel like gaining my lost health wouldn't be an issue. This would also be beneficial against bosses and would cut down on swig times.
https://preview.redd.it/b1897uvfszoa1.png?width=200&format=png&auto=webp&s=8dc1e0fdac45c250fe446c9252344dd341ad0788
If you have any feedback or suggestions, let me know! Also, share what you created if you believe it's similar to my build.

Spoilers for Elphael, Malenia's boss fight, and the identity of the Gloam-Eyed Queen.
The Spires
The Tarnished Archaeologist theorized that the purpose of Miquella's golden needles was to kill Godwyn's corpse and give him a true death. If I recall correctly, part of the theory was that these needles would also be used to kill the Erdtree. The method is based on the folk practice of hammering nails into stumps, which is believed to kill them and whatever was left of the trees after being felled.
I think this might, in addition, be the inspiration behind Elphael's structure and shape. From the top, i.e. the view seen on the map, Elphael can be seen to comprise a large circle (the brace of the Haligtree) and a number of spires which jut out linearly at various points along the city's circumference. To me this looks like a series of nails surrounding the cross section of a tree trunk.
https://preview.redd.it/r9f0tei1l6oa1.jpg?width=2560&format=pjpg&auto=webp&s=b8f5cfbb156ae3c6f520eeefafb9edb4e21a6008
Some more evidence for this view is that each of the spires has a number of smaller protrusions jutting out from it vertically, on the tier that is close to the top of the spire. I would include a picture here but I've already reached the 20-photo limit for this post, so I'll include a link to it below, at the bottom of this post.
I understand this seems like an absurd architectural design choice, since Miquella probably wants the Haligtree to thrive. However, it's possible the design is meant to communicate something about Miquella's ambitions in other areas, even if he does not seek to apply the nailing technique to the Haligtree.
Alternatively, maybe the spires are just meant to grant additional support to the brace? This seems more plausible, since again the needling technique was presumably not meant to be used on the Haligtree. Leyndell does not have this same architectural feature, so perhaps Elphael is an attempt to achieve a more fortified city, and stronger brace?
Rot and Snow
The section of Elphael with the rot swamp seems to also contain snow, or perhaps a fine white fungus that resembles it. (This in turn reminds me of the white fungus particles floating around throughout much of Nausicaä of the Valley of the Wind, which also deposit into surfaces resembling snow.) There's also the possibility it could be ash.
rot and snowlike substance inside the Haligtree
This pairing of rot and snow is likely a reference to Norse mythology, and more specifically the Élivágar, which are icy rivers containing poison or "yeasty venom" called eitr. Eitr is produced by the snakes in the Norse mythos, and is the creative material from which Ymir was born; it's said Ymir was created from the dripping of this poison from the Élivágar. Remember that poison and rot are adjacent or perhaps identical forces in Elden Ring; and the same is of course true for snow and ice. The coupling of these two natural elements was also featured prominently in Dark Souls III's Painted World of Ariandel, which was like the old Painted World of Ariamis from Dark Souls, but with the addition of red, scarlet rot.
Since Ymir was the first jötunn (giant), and Malenia is found at the bottom of the rot waterfall, it's possible that she, or at least her placement here, is meant as a parallel Ymir. Malenia is much larger and taller than the player character, and is indeed a kind of giant—though this is true of all the demigods, barring Miquella. One could alternatively view Miquella's husk as analogous to a jötunn , however.
In addition to Norse mythology, I believe this area was also inspired by Christian ideas. It appears to be used for the purification of rot, with clean water being directed toward the drainage channel, and the rot flowing down the waterfall into Malenia's boss area (though the water at the base of the waterfall is pure, as was pointed out by Quelaag). The theme of purification, with the blood-red rot and white snow, reminds me of the Christian saying: that with his blood, Christ "washed our sins as white as snow." In this case the "blood" might be more symbolic of sin than Jesus's blood, but it does seem probable to me there was Christian influence on the design of this area. (I'm sure you don't need reminding that Miquella and the Haligtree incorporate a number of Christian ideas and images.)
One other thing on ice and poison: this duality is also seen in Elden Ring's snails. The four types of snail seem to be divided into two pairings: one of life and death, seen in the deathblight and spirit summoner snails (Garrulous_Goldmask recognized this pattern in his snail video), and one of poison and ice, seen in the venom-spewing and ice-breathing variants.
The Naked Woman Relief
The first relief I wanted to discuss is the carving shown below. In my view, it is a likely candidate for the most densely meaningful symbol in Elphael. Accordingly, this section is going to be the longest in this post, by far.
https://preview.redd.it/kirgm9q5l6oa1.jpg?width=1145&format=pjpg&auto=webp&s=6690537e1b34b413fb0bac9b194b48db6a562494
What I see in this relief is a topless woman flanked by snakes, rising out of a flower. Above the woman's head is a bird in a container of some sort, possibly a cage.
There are multiple interpretations of the snake-and-bar pattern that are important. First, the shape resembles that of a stethoscope. This would tie into the medical theme of Miquella and the Haligtree. Elphael contains a great deal of caduceus-like iconography, such as in the Haligtree banners, the shape of the Haligtree itself (two trees spiraling together), and Miquella's needle. Miquella has the lifelong goal of curing his sister's sickness, and allows his disciples to rebirth themselves through baptism, which is a rite used to attain physical and spiritual purity. The primary color associated with Miquella is white, which is often used to connote ideas of cleanliness.
Edit: After reviewing the real caduceus symbol (shown here), I can see that this relief resembles it much more than I thought. In addition to the two snakes, there's also the woman's hair, which I believe is meant to resemble the pair of wings seen at the caduceus's top.
(a) The placement of the curved lateral bars in the relief is interesting, because it makes them seem like a failed attempt at censorship. Instead of covering where the woman's nipples would be, the bar is just beneath them. The same is true of the bottom two bars and the small curve on top, which are too low to cover her groin. (I might even see a vagina at the bottom of it). The ineffectual censorship could be an indication of movement; if the bars normally cover the woman's breasts and groin, their position below these areas might mean she is ascending, and perhaps transcending her inhibitions.
Since Malenia only bares her chest in her second phase, which occurs at the same time she rises out of her flower's bloom, I think the woman in the picture could be Malenia, and that the flower at the bottom of the relief is a scarlet aeonia. I also think the two smaller flowers on the side could be the bloom of the unknown valkyrie found before Malenia's boss room, and Millicent's bloom which only grows if you follow certain conditions in her sidequest.
Actually, since there are three blooms, and the figure is rising from the largest of these, there's a good argument to be made that the relief is depicting Malenia's transformation into a true goddess, and that the two smaller flowers to the side are her own, previous blooms. Gowry says that Malenia will "ascend" to godhood, and that's exactly what we see in this carving. Also, we can see her physically ascend as she grows wings in her mid-fight cutscene.
(b) There is another candidate for the identity of the woman. One of the first characters and candidates I thought of when observing the relief was St. Trina. This was because of the wild, upward-oriented hair the two figures share.
St. Trina's torch
It's possible the hair in the relief of the woman could be some kind of headdress, but I do think the hair is meant to resemble St. Trina's, mainly because she is accepted to be a counterpart to Miquella, and thus has a significant narrative relation to Elphael and the Haligtree.
I've considered that the woman's hair might itself be snakes. This came to mind before I had even noticed this etching, and was initially a response to looking observing St. Trina's design on St. Trina's torch. The mythological parallel that came to mind was Medusa, who has snakes for hair. This is not a new theory, as I've learned, but quite an old one. The relief is further evidence for it, given the placement of the snakes right next to the woman's hair. (I'd like to share some more evidence for the Medusa theory, even though many have already accepted the conclusion. First, purple is consistently associated with fear in Elden Ring; I mention this in the 4th part of my GEQ and gravity series. Second, the torch itself is made of stone. This relates to Medusa's ability to turn her victims to stone by looking at them—in this case, with her third eye. Finally, the name Medusa starts with M and ends with A, like all of Radagon and Marika's children.)
This identification of the figure with St. Trina is partly compatible and complementary with the previous theory of the blooms; the blooms are common to both models, but St. Trina is substituted for Malenia.
Miquella's husk above Malenia's bloom
For a while I wanted to share my thoughts on the above image, even though I figured many had already come to the same conclusions. The idea was that the scarlet aeonia is an analogue to the Crucible, and Miquella's form in the Haligtree above it is analogous to the Erdtree. The scarlet aeonia is red with swirling petals, which is often how the Crucible is depicted: as red, or as a spiral. The Erdtree is above the Crucible since it was seemingly grafted onto it, and here too, we have a section of tree above the Crucible part.
It could also be argued that the pattern and positioning of life and death in this scene matches that of the Erdtree. The Crucible is close in nature to life itself, despite being fueled by violence and bloodshed. The Erdtree on the other hand is probably dead, considering it was burned before, is ghostly and transparent, is made of memories, and has a stony, i.e. petrified appearance. Here too, we have a dead tree on top, and a living organism below it: a flowerot. And in the same way that the Crucible feeds on bloodshed, Malenia regains HP by injuring her opponents. (As a minor note, Waterfowl Dance is a spirally move, which is also somewhat evocative of the Crucible.)
(c) In addition to mirroring the Crucible and Erdtree, I think the scene is a depiction of what we see in the etching of the topless woman. If Miquella is St. Trina, or her counterpart, I think the woman rising out of the flower is Miquella/St. Trina, and the flower is Malenia herself, i.e. the scarlet aeonia. Note how Miquella's tree form, in addition to being female (since it has a womb), has tendril-like roots for hair, which has some visual overlap with the hair of the woman in the relief. Also, look at how the bars in the stethoscope-like shape seem to surround and focus on the abdomen of the woman; almost like the womb is being targeted in an operation.
Notably, the snake-bar pattern has some resemblance with the upper half of the gravity sigil, which is the same fundamental shape as the moon's rune.
Observe how the bottom two bars are closer together than the middle and top bars, in both the sigil and relief.
Moreover, you can find three concave-up markings to correspond with the lower half of the gravity sigil, which makes an intentional resemblance to the gravity sigil more likely. The full shape is basically contained within the relief.
You can compare this picture to the unedited version to verify the rune-like markings I've outlined.
A third interpretation of the snakes and bars is that they might be a depiction of the Twinbird. There is a pattern in Elden Ring of two birds being paired together. Of course, the snakes could just be the caduceus which would correspond better than two birds... but to my knowledge, twin snakes, explicitly depicted, are less common in Elden Ring than twin birds. Furthermore, if you've looked at the deathbirds, or the snake-bird statues in the Temple of Eiglay, or were convinced by my theory on the Flightless Bird, you probably know that snakes and birds are often treated as interchangeable in Elden Ring. For these reasons, it's possible the snakes are the two halves of the Twinbird.
The gravity and Twinbird ideas are both components to my next theory: that this figure is St. Trina, but also Melina. I recently shared some ideas that support the Melina as St. Trina hypothesis, which I invite you to read if you want to know why I'm persuaded by it. With respect to the Twinbird component: Melina has some association with the Twinbird since it's likely she is the Gloam-Eyed Queen or her successor, and has a crow's foot around her gloam eye, and crows and deathbirds are known to be related via the Ravenmount set. Also, gloam is purple and so is the Twinbird in all likelihood. That being said, the Gloam-Eyed Queen is also associated with serpents, e.g. the Temple of Eiglay and the godskins who have snake physiology, so the Twinbird might not be a necessary piece of this theory.
The gravity sigil is also gloam, and I have a series of posts explaining why I believe the Gloam-Eyed Queen and gravity are connected. Some evidence for this, summarized, includes the "weighty" description of the black flame, the shared black and white color scheme of the godskins and gravity enemies, and the fear motif common to Destined Death and gravity enemies.
In the Melina/St. Trina interpretation, the flowers at the bottom of the relief are not scarlet aeonias, but miranda flowers. The flowers in the etching look more like miranda flowers than scarlet aeonias, and rotted miranda flowers can be found through the Haligtree and Elphael. Furthermore, the giant miranda sprout shown below is found very close to multiple etchings of the woman, side-by-side.
https://preview.redd.it/2j9bnj3m1moa1.jpg?width=2560&format=pjpg&auto=webp&s=25e05151571bf5880aa6abd174c87d422b2610e8
In this interpretation, the central flower is a giant miranda sprout, and the two on the side are the smaller, regular sprouts. In fact, that is almost exactly what we see in this location: a large miranda sprout in the center, with one smaller sprout on one side, and two smaller sprouts on the other.
What ties this to Melina is that she has an ability called Miranda's Prayer, which she can only use in the fight against Morgott. Initiating the attack causes a golden tree to appear and rain light (it's similar to the light attack used by the giant miranda sprouts). This is a fairly well-known cut item, as it used to be obtainable by the player as a talisman.
What ties this to Melina is that she has an ability called Miranda's Prayer, which she can only use in the fight against Morgott. Initiating the attack causes a golden tree to appear and rain light (it's similar to the light attack used by the giant miranda sprouts). This is a fairly well-known cut item, as it used to be obtainable by the player as a talisman.
Now that I've looked at this picture, I can also see a resemblance between the petals of the flower surrounding the head of the woman in the talisman, and the hair of the woman in the etching.
Another key observation is that St. Trina has a flower above her head in her torch depiction. This seems to have some similarities with the flowers in the Elphael relief, and the flowerlike hair seen above the woman's head.
If Melina is St. Trina, who is also Miquella's counterpart, it's possible that more than one of the theories laid out so far could be true. The relief could be depicting Miquella's tree form above three scarlet aeonias, and it could be St. Trina/Melina rising from a miranda flower. These theories are particularly compatible, but even though the Malenia theory differs from these two in a key respect, I still think it's quite likely this perspective is correct as well. The three flowers do not seem to be a coincidence, given the significance of the three blooms preceding Malenia's ascension.
One more thing on this relief: the bird seen above the woman's head appears to be an owl, which likely connects to the slumbering egg, a crafting material dropped by owls. Miquella sleeping in his cocoon involves both slumbering, and an egg.
More Flowers
Elphael has some of the greatest floral diversity in any area; it resembles Jarburg, in this sense. My take is that this variety symbolizes Miquella's willingness to accept all things, and creatures.
https://preview.redd.it/1vd7fbrhl6oa1.jpg?width=2560&format=pjpg&auto=webp&s=2111aae505bb9cb3719f73ab0845549a0ade1366
I've recently understood, more explicitly than before, that a defining quality of the Crucible is the lack of distinction between species, or even organisms which are normally separated at higher levels of biological classification, e.g. families, genera, and kingdoms. For example, roots, branches and antlers used to be found on the same creatures (the ancestral spirits). The same applies to flowers, for example in the guardian enemies, who have flowers growing out of them.
Thus, if flowers are viewed as parts of other creatures, and the Haligtree is in some respects a return to the Crucible, then the cultivation of various flowers simultaneously represents the cultivation and growth of organisms more easily recognized as sentient: Albinaurics, Misbegotten, etc.
Fountain and Door Designs
The doors in Elphael feature two faces: an infant's or young child's on a shield-like pattern, and a menacing face below it.
https://preview.redd.it/vi7ny2til6oa1.jpg?width=1625&format=pjpg&auto=webp&s=9900abc2e60ed46c045e9f7c1b204538a3a89003
My take is that this door is, more or less, a before-and-after image for the effects of Haligtree rebirth.
The face on the bottom kind of looks like a skull, which might be because death is required in order to reincarnate. This could also potentially explain the frequency of skull designs seen in Elphael. I've theorized before that the reason the skulls are often upside down, is that they are a depiction of death being overturned, much like how Jesus conquered death on the cross, and granted humanity the chance at a new life in heaven, in a new, reincarnated body.
However, while the bottom face does resemble a skull, it also looks apelike to me; I think this face belongs to a demi-human, who are really the only simian creatures in the game. Although the demi-humans aren't present in Elphael, they competently represent the outcasts of the Golden Order, who are accepted by the Haligtree in spite of their lower, Crucible nature. This is why the demi-human face is below that of the child. The child is ascended, while the demi-humans and Crucible races are depicted as lower (both spatially and spiritually).
With regard to the transformation process, I've speculated that the ribbons and clothlike patterns below the demi-human face are part of a baldachin, which most players will remember from Fia's Baldachin Blessing. Baldachins, though they were used for thrones and altars (like the Prince of Death's throne), have also been used for beds, in which case they would more commonly be known as canopies. In Elden Ring, Fia is associated with sleep, since we can choose to rest with her, and since the Deathbed Dream is accessed through Fia, and is found among purple water (which here signifies sleep, as Hawkshaw identified in his colors video). In turn, sleep is connected to rebirth; this is made clear by the juvenile scholar clothing description, which states: "Rebirth is as sleep to them, and with each awakening, memory fades into oblivion."
https://preview.redd.it/osap5ptkl6oa1.jpg?width=332&format=pjpg&auto=webp&s=19b0c650339d5e11b70f8c19a08204668e494b0b
Of course, if baldachins are linked to sleep, we shouldn't be surprised to find it in an area important to St. Trina.
Another factor that ties the demi-humans to St. Trina is the purple eyes of the demi-human queens. We already know that the demi-humans have been taking on increasingly human characteristics, evidenced by their adoption of magic, and their tutelage by the sorcerers in the Hermit Village on Mt. Gelmir. This could relate to the transformation of demi-humans into humans, depicted on Elphael's doors. Alternatively, if the purple eyes are not referencing St. Trina (whose torch depiction has a purple eye when illuminated by its flame), they might be a reference to the Gloam-Eyed Queen. (The demi-human queens are literally gloam-eyed queens.)
The design of Elphael's fountains confirms the symbolic link between the child and purity.
https://preview.redd.it/0z5wjxcml6oa1.jpg?width=2560&format=pjpg&auto=webp&s=ce73ce73d15f06aac01cc68a1ee87bcb8264dde9
You can see how similar the face of the child seen here is to the infant's face on the doors; and this head is also set against a shield-like design.
As has been discussed, the water in Elphael is purified through the drainage channel, and is potentially filtered out from the liquid rot, or at least diverted from it. So water, without rot, is a symbol of purity. If the purified water spouts from the child's mouth, then we can reasonably infer that the child (likely Miquella) is also a symbol of purity.
The Bell Tower
This one's pretty simple. My interpretation is that the bell is, or represents, a spirit-calling bell.
https://preview.redd.it/au54xgnol6oa1.jpg?width=2560&format=pjpg&auto=webp&s=532e490d909f8daa6343e99d72372345815eacbd
The ghosts summoned through ashes of war are a very faint purple, which is similar to the light purple flame of St. Trina's torch. I also take this is as additional evidence that Melina is St. Trina, since we receive the spirit-calling bell from Ranni, who says it was given to her by Torrent's former master. This is likely Melina, since it's her we see riding Torrent before she bequeathes him to us.
The Northern Door
https://preview.redd.it/gda8vblpl6oa1.jpg?width=1912&format=pjpg&auto=webp&s=b1407ab8a19f47138274615fb7035ce43c0d6f17
This door is found right next to the Elphael Inner Wall site of grace. I find it to be one of the most beautiful sights in the game: the warm, golden light shining through the crack in the door, beckoning the player to enter while also retaining its secrets, since the door cannot be entered. Something about the door being open, but not completely, makes the view so appealing to me.
The door likely has some significance, because while it has the same design as the others in Elphael, it's the only one of these that has these other aesthetic features; the only one to have golden light shining through it, and roots or vines surrounding and infiltrating it. Another hint at its significance is that it is located at the northmost tip of the map—not just the map of Elphael, but of the entire Lands Between.
One possibility is that the door will be used to access the DLC, which we now know will feature Miquella. Another idea is that it is a geographic and thematic opposite to the southernmost location in the Lands Between: Castle Morne. Morne, of course, represents sadness and loss. The Haligtree is a means to transcend this despair, and find happiness in the next life. So the light from beyond the door could be heaven, or the "light beyond the veil." In fact, this particular door looks remarkably similar to the design at the center of the baldachin's blessing icon.
Speaking of Castle Morne, both it and the Haligtree have a high population of Misbegotten. Perhaps the rebellion at Morne could be viewed as the start of their redemption, and their entry to the Haligtree as its conclusion; the great physical difference between the two locations could be showing how "far" they've come, in multiple senses. The northern and southern placement of the Misbegotten also might reflect the alchemical saying "as above, so below."
Objects of Worship
In the lower area of Elphael, soldiers can be seen sitting by headstones in the graveyard, perhaps paying respects to fallen soldiers. All of these soldiers are located on one side of the cemetary; on the other side are more headstones, but this times the graves are attended to by Kindred of Rot. This likely signifies that the Kindred are being integrated into Miquella's order, but that this process hasn't been completed yet. The Kindred are basically in the segregation stage of the movement toward equality, in that they are technically accepted by the order, but nonetheless kept separate.
I also think there's more to the fact that these Kindred are seen around graves. First, they do not give the impression of being somber or feeling grief the way the Haligtree soldiers do. One of the infant Kindred has its arms raised in front of a headstone, similar to the worshipping Kindred in the Sellia Crystal Tunnel and Grand Cloister.
infant Kindred worshipping in front of a headstone
This Kindred, instead of showing respect to the dead as we would expect, is worshipping the grave. This is because death is what gives rise to rot; death is the genesis of Kindred as a species. This is proven by the Caelid Waypoint Ruins, in which a unique basement area can be found, containing open graves. Within these graves are rot and eggs, and the room is filled with baby Kindred, which surely hatched from these eggs. (This is the only other place that infant Kindred of rot can be found, other than this lower region of Elphael.)
There are two other notable sites in this graveyard. The first is two infant on both sides of a larger Kindred, raising their arms toward it. The second is a scene of both child and adult Kindred bowing in front of an adult Kindred with its arms stretched out. This Kindred is standing above them on a rock, kind of like its giving a sermon to them from the pulpit. This wouldn't be surprising since this is taking place right near a church; they seem to be having one of those outside sermons. Between this Kindred and its audience, is a corpse with a Numen's rune.
I believe these two scenes are related, and that the common theme is growth. The smaller Kindred are showing reverence to their larger elder, and the other Kindred mentioned are praising the power of the Numen's rune. That's because this rune is associated with abnormally large proportions, e.g. the giant ants which are the best enemies to collect them from. Maybe growth is treasured because rot itself is a growth? This could be said of really any organism, so I'm not completely sure about this.
It's not uncommon for churches to be found in cemeteries. For the Kindred of Rot, though, I speculate the church may have actually been established in the graveyard intentionally, instead of the graveyard cropping up around the church. I say this because, again, death is the origin of the Kindred's existence, and as such they likely view graveyards are holy places. The church is only inhabited by Kindred, not the Haligtree soldiers nearby, so it does seem like the church is used by the Kindred specifically.
Speaking of the church, I had something to say about its windows.
Stained glass and mandala in the Kindred's church; also... this is probably a complete coincidence, but 'mandala' is another word that starts with M and ends with A.
To my eyes, these stained glass windows are more vividly and variously colored than the windows in Elden Ring's other chapels and churches. What this represents, I maintain, is the acceptance of all forms of life to the Haligtree; each color could be viewed as a type of creature, or way of life. Along these lines, the circular window could be considered a mandala, which is a type of religious symbol used to express broad religious ideas, worldviews, and cosmologies. So in addition to the colors themselves, the mandala pattern is inherently a symbol of holism.
Baptismal Fonts
Much can be gained from comparing the design of Elphael to Leyndell, from which Elphael took inspiration. For example, in addition to including massive trees with the cities serving as their braces, both cultures have the same elevator platforms. As an example of meaningful contrast with Leyndell, you could say that the candle design in Elphael reflects a return to the Crucible, since its candles use real fire, not the artificial candle lights seen in Leyndell.
This method might be helpful when applied to the baptismal covering structure in Elphael.
baptismal covering structure
In Leyndell, the baptismal fonts are covered by these small, domed structures. Similar structures can be found in Elphael, except there are no basins beneath them. One potential solution, and the simplest, is that the fonts were removed in order to make them easier for the Albinaurics to access. However, there are many more fonts being used by Albinaurics than there are font-coverings. That Elphael has only one of these structures is likely an indication of its importance.
Although the basins are missing, there is still water beneath where they would normally be. My highly speculative take is that, in addition to being transferred for the sake of the Albinaurics, the absence of the baptismal fonts from these structures symbolizes Elphael taking a step beyond Christian humility: one in which baptisms are performed with ground water. Edit: recently had the thought that this might be a reference to the miracle of Jesus feeding the multitude. Again, there is only one font covering, but many of these are found in the room right next to it, which contains the transforming Albinaurics
Acceptance, Rejection, and Conversion
It's probably confusing that in some places I've argued for Miquella being accepting of rot and those who were outcast by the Order, and in other places say that Miquella was trying to purify the outcasts and convert them. One potential solution is that the contradiction is intentional; Lazy-Poem6488 theorized in their recent analysis on this topic that Miquella and Elphael express purposefully contradictory ideas, because contradiction is the result of true open mindedness and tolerance.
This could be true as a general motif in Elphael, however in this context I think it's more likely that Miquella's acceptance and rejection of those rejected by the Order occurred in two time periods. The first would be a period of attempted conversions, while the second would be one of unconditional acceptance. Elphael's original architecture would reflect the former, while some of the repositioning and modern changes would express the latter.
An alternative to this idea, and one that I'm finding more likely as I ponder it, is that Miquella may have both rejected and embraced the disciples of his Haligtree, but in a manner that is non-contradictory. That is, Miquella may have accepted the tarnished and maimed, but conditionally—more specifically, under the condition that they follow him, convert to his order, and purify themselves through the Haligtree.
A similar phenomenon occurs in a number of religions, with Christianity being one example. In Christianity, God accepts everyone and anyone—so long as they submit to him, and follow him only. This pattern is repeated by an unfortunate number of Christians, who are presented (not just by themselves, but by society in general) as tolerant and charitable, despite their tendency to employ these virtues as a means of converting—i.e. transforming, rebirthing—those who have not yet received God's grace.
While I'm not entirely confident in this interpretation, it might fit well with FromSoft's criticisms of Western religions, and Christianity. On the other hand, it does kind of seem to me like Miquella is meant to be a "true" Christlike figure, who is at a higher and more genuine level of spirituality than, say, Corhyn or D. Miquella also has a number of traits in common with Goldmask, and Goldmask is certainly not characterized as a fool, or as being corrupted by faith.
The Leaves of the Haligtree
The branches of the Haligtree, as well as the branches resprouting from the roots in Deeproot Depths, are growing oak leaves.
https://preview.redd.it/h3elrv6wl6oa1.jpg?width=2560&format=pjpg&auto=webp&s=63156238d4aeb6db49ad404b79e35c93fc152a2a
One explanation for this is that the Haligtree is genetically related to or descended from the Erdtree, and would naturally grow the same type of leaf. Another idea I had is that the Haligtree might have been invaded by the Crucible roots in the Mountaintops and Consecrated Snowfields. I originally only noticed the oak leaves on the smaller trees in Elphael, but I realized they're also present in the upper branches of the Haligtree. In my opinion, this makes the invasion theory less likely, though I haven't ruled it out yet.
The user cheese_dogg recently wrote a post which concerned this topic, but that also covers other theories relating to the Erdtree, Greattree, and grafting. I think it's among the best theory posts ever written on this game, so I definitely encourage you to give it a read. It's called "Odd Leaves, Chimeric Plants, and Some Connections to the Crucible".
Link for the thumbnail: https://imgur.com/a/3xTZ3k3
Additional pictures: (spires and the rotted miranda flower): https://imgur.com/a/2FbVwan