I did mine in two seperate groups, did 1 pally 4 shamans, then 1 shaman solo
then dk, mage, priest, druid, lock in the second then put them together.

All of your groups will work for pvp, but the second group would be good for pve, espically if you took out a shaman and added anther tank.

But as always, play what you like, whatever is fun for you