I've been so focused on how meh sorcery is for mages...

Aery, mana or ulti speed, cdr+bonus ap on cdr, scorch or water walking or if you think it will go to REALLY late game, then that other thing.

I like these best on most enchanters.

Depends on the enchanters. Made sense on, say, Sona (who used Aery rather well), but Guardian was a better choice on Soraka.