The reason I didn’t suggest Seshat is because she wouldn’t work well with Finley. If Seshat and Finley are charged up in the same turn, and he fires before Seshat, there wouldn’t be a problem. However, if Seshat dispels the buffs from 3 enemies the turn before Finley is charged up, then his special’s power would be significantly reduced.
I also wouldn’t use Guin + another healer, that’s too much healing, imho.