good healer

Azama is the best out of yours. Upgrade him to 5*, give him Pain+ and the Savage Blow C skill (Camilla has it at 4*) and the Savage Blow Sacred Seal and he’ll be a very useful AOE (area of effect) fighter

considering only the stat spread, I think you would like either azama or maria.
Maria have good spd and res (over 30) in 4*, she can serve as a semi-tank for magical hits.
While Azama 3* is slow, he can tank some hits considering his 39 hp pool, nifty def and so-so res, and raising him to 4* will do a better job at that.
Lachesis have high atk compared to many staves,
Lissa is slow but her def and res spreads evenly,
Serra's stat is similar to maria, except with less spd, less hp, but more atk stat.
Sakura is very all around in her stat, prefering res than def.

Think that's the gist of it, I hope it helps.