For PvE:
You'll need a healer at some point. I'd suggest keeping your Pally tank and adding 3 casters of your choice, plus a Resto Shaman. The totems are simply too powerful to ignore, and you can always dote on your other 4 toons if you can't dig the tail.

For PvP:
Start with 5 non-cloth ranged dps of your choice (Hunters?). If you get frustrated with macros and such, or if you get bored, try casters or melee.