So I'm running this duo right now, after hoping I could find some advice on this online I did some trial and error and found something I really like for levelling.
The tank is a paladin/warlord/reaver in instances, but I swap in a beastmaster soul whenever I'm out questing. The healer is a chloromancer/elementalist/dominator.
The tank is self-explanatory, but the healer...

the true wonder of it is if you take up to level 6 in elemental summoner and level 8 in dominator, you will never ever ever be stuck in a situation where you're just unable to cast, waiting for mana to come back.

http://rift.zam.com/en/stc.html?t=0zRsq.Vdbz.Mcc.Vz (level 19 version)

Elemental offers "Revitalize" which is like evocation (only usable out of combat), and Mana Wrench which returns 18% of your mana over 6 seconds. It's a great talent for a healer to have. Plus you have your little earth elemental pet running around. Oh, and you can squirrel people.