The fight against Tsukuyomi when one must do the stacking mechanics while dodging (phase 4 at least) could become easier for WHM to heal if Presence of Mind is allowed to instant cast like Lightspeed; same with similar fights.

Lowering PoM's cooldown time would be nice, and if they added an effect to it (like a variety of Surecast) making it so one could move while casting (but can still be drawn in/knocked back if not having used Surecast) in addition to the reduced cast and recast time (without LS instant cast) that could also work I think.

WHM have Thin Air, Assize, and Lucid Dreaming to regulate mana, so overwriting a raise isn't really an issue in that regard, I think...