The stuff I've run around with so far
Mage or Mystic + Provo: Summons get the HCI and DI bonus as well as the stats and healing
Tamer Peacer: The damage reduction on the tames helps alot/ But I dont play a tamer very well so I can't speak to the real usefulness
Disco Mystic/Disco Mage: Very Mana intensive but despair and plague make a nasty combination on low resist players.
Tribulation drops HCI when fighting dexers and archers. (Not to mention the 30% damage and combining with a flame strike can be up to 40+ damage on an uncursed player. (Sleep also stacks with tribulation which is also a HCI debuff)
Provo Mystic/Mage : Invigorate is nice for healing on the run