I play a Horde Shaman on Gorgonnash. I knew I wanted a hybrid class before I started, and found out afterwards that Shamans are the most complained about by Alliance. They're total badasses. I definitely recommend you go Horde, and roll on a low-population PvP server. PvE means you PvP only when you really want to, but it sucks out a lot of the tension from the game, and after a while it would get extremely boring not being able to kill the guys who keep taking your monsters/loot and laughing at you.
I never thought I'd enjoy a point'n'click game.. ah well