I'd like to see a widened area of effect for white mages using white magic and black mages using black magic. Well, not entirely sure on the latter, black mages might have a better idea on whether or not that would be good or bad considering it could affect mobs you aren't in battle with and could result in problems. White magic obviously doesn't have that kind of issue.

EDIT: Also, Bard - bonus to enfeebling and enhancements. Naturally.