I've designed the manabase to try to minimize self-pain from fetching. In a meta full of Chalice of the Voids set to 1 on turn 1, the uncounterability is pretty big as well. Most of the creatures in the deck, including both the black creatures, are creature type Cleric, so that's the most common type to name. All but Ayli are also Human, so if you don't need early fixing for her but want to play Martyr into Serra Ascendant in a land-light hand, Human can sometimes be the call. Flagstones are an all-star for pain-free color fixing, and synergize well with the Ghost Quarters for extra fixing options that flex to help not lose to Tron and Eldrazi.
Hangarback Walker is there as a <=1 CMC target for Ranger of Eos, which can produce multiple targets to sac to Ayli in the late-game. Plus he gives a slight bit of wipe resilience and gives you answers to defend against Etched Champion.
I'm experimenting with Liliana, Heretical Healer as a 2-of right now. 2 black is a little rough, but she doesn't need to come out early and is a Cleric so I think it's doable. She can get back Martyr for extra life gain, a dead Ajani Pridemate or Serra if you need a threat, or even Hangarback (x=0!) if you need to recur some sac fodder for Ayli or chumping.
Sideboard is also local-meta-tuned and varies week to week, including the most common cards for answering various matchups I'm concerned with right now. The SB card choices aren't intended necessarily as a suggestion for anyone else building this list, but more the ones I've included for now offer some possible choices based on the matchups I expect to see. I might add some hand disruption (Thoughtseize, Inquisition), if I'm needing them as answers to non-graveyard combo decks. I don't love that in this deck though, since we really want to be casting a soul sister on turn 1 if at all possible to start gaining life and curve out. Thoughtseize also further sets us back against the 30 life goal to turn on our exiling and Serra Ascendants. Nevermore may be a combo catchall more aligned with the deck's curve and goals, or possibly Leyline of Sanctity (not so much worried about burn, but for stuff like Grishoalbrand, Jund/Junk hand disruption, storm, some others).
