Personaly I would stick to the mage. Slow spell, improved counter spell, sheep, INSANE dmg(now at lvl 67 with normal quest gear, arcane blast is critting for 3K3 without trinkets..) You got less chars ofcourse, but still... It's very versatile.
Btw, portals ? Free food and drinks?(although I never use it due to mana/heal totems) frost nova for mobs that are running off.... list is endless

Good luck.