questions (and is there a FAQ anywhere?)

[Taqwus]

Some units do heal battle-caused afflictions naturally; these are mostly Pangaean units and certain pretender types, and have a particular icon representing recuperation. Immortals also probabilistically heal over time, regardless of whether they're in their own dominion.

In addition to EA Ermor Shroud priests, and Arcosephale priestesses, Faerie Queens and the TC immortal healer (all eras, if memory serves... but it wouldn't surprise me if they're swapped out in LA in some patch), there's a formidable Sauromatian heroine who can heal troops.