Which healer to use until Endwalker and Sage?

[Radacci]

I do have all the casters at 80 and I have Sch at 80 with Whm at 77 and Ast at 70.

Why are you asking which to play, when you already have SCH at 80? pretty sure you know how they play.
I'm guessing that's what you liked most since it's ahead of the others.