My mages kinda sucked at 19. Sure 4 fireballs would kill people, but I rarely got a chance to cast em all. My 5 druid team was much better, because of 10x HoTs, so I could immortalize my teammates, root the enemy, and spam wrath/moonfire.

Mages will probably do better later though, but for the 19 bracket, id skipt it.

I have 3 priests, so I might try doing something with them someday, if I ever get around to leveling the other 2...