Can only speak from a PVE point of view, but I would say hunters or locks, mainly because of the pet tanking aspect, because as long as your friends are there its great, but when they are not online and you want to get on, I just found it easier to do those harder quests with a tanking pet. Thing is once you get bitten you will have all 11 classes, in different combo teams til you come to the one that suits you, but good luck and keep on going

just my 2 penny's worth :P