i'm with Marky on this one, i never understood the use of magic besides healing spells in these games since physical attacks are infinately better due to not relying on something as limited as MP... sure you can very slightly scratch an entire enemy party with one spell but in the long run it really adds nothing besides pretty lights... the only Black Mage that did it right was Lulu form FFX she was the only Black Mage i ever got any real use from as her magic attacks actualy did some damage...
as for my favorite class i actualy don't have one but i love monks, dragoons, & warrior classes... mage classes are a waste of turns unless they're healing...