I'll play:

BLU: Enhancing Blue Magic Duration, Blue Magic Damage
WHM: Amnesna, Charmna (Can be on long timers), Elemental Barspells II, or just enhance current barspells with JP.
THF: Make TH7-13 Not pretty much negligible somehow.
SAM: Increase Chance of Third Eye not being lost after an attack is absorbed with Seigan up.
GEO: Entrust - Enhances the duration of the entrusted Indi spell, Regain.
RNG: Decoy Shot Duration