I have:
Top : Groh, Seong Mi-Na.
High-Mid: Siegfried, Nightmare, Ivy, Yoshimitsu, Sophitia.
Mid: Talim, Voldo, Zasalamel, Kilik, 2B, Azwel.
Low-Mid: Xianghua, Mitsurugi, Taki, Geralt, Raphael, Cervantes.
Low: Astaroth, Tira, Maxi.
Personally, I think this is one of the better balanced SC games there has been at initial launch. I'm inclined to cluster the majority of the characters firmly in the middle tier--though its worth saying that a few of those that are unbalanced have very significant problems, either through intended moveset mechanics that have proven to be unbalanced or unintended issues (such as errant hitboxes causing whiffs where they obviously were meant to connect, that sort of thing). When deconstructing anything in a more minute fashion, I think we have to provide any such analysis with some serious caveats if we are going to try to say anything meaningful only a little over two months into the general release and when the post-release patching/balancing work still very much in its initial stages. So I personally would only speak to broad strokes and keep my categories to three --though this will still leave the majority of characters placed (accurately, I feel) mid-level:
Top: 2B, [Makes me] Groh[n]*, Ivy*, Nightmare, and maybe Yoshimitsu
Middle: Azwel, Cervantes, Geralt, Kilik, Maxi, Mitsurugi, Raphael, Seong-Mina, Siegfried, Sophitia, Taki, Talim, Voldo, Xianghua, and Zasalamel
Low: Astaroth and Tira
* Probably not entirely exaggerative to say these two are close to broken right now. Honestly, I try to credit Namco with the expert perspective when I find myself in disagreement, but seriously, why did already severely OP Groh get like twenty adjustments in one patch, and every single one of them buffs!? And as for Ivy, was the lead designer who engineered her moveset an actual sadist who is getting off on what he did with her--holy god!
I base this mostly on feedback coming from the various branches of the community, particularly well known tournament players or at least those who are well-informed on high level mechanics, but I will admit that a couple of the highs are informed at least as much by some of my own idiosyncratic experience. By comparison, the low values I give to Tira and Astaroth come from the significant number of players whose experience and objectivity I respect who have said there are just broken features here that turn a good potential character into mincemeat in high level play. Anyway, I believe this listing is roughly reflective of consensus as I've heard it expressed so far (but of course that is easier to accomplish with a simple three tier structure, and early in into balancing).
