I am quite experienced with the game and playing more complex calsses/specs isn't a problem for me.
I have played a Death Knight, a Priest, a Warlock and leveled a Warrior, Paladin and Druid to 85.
I want to get serious about PvP and get into RBGs and Arenas, and I want to be a damage dealer, although the possibility of healing could be nice, but definitely not required.
I like it when the gameplay is extremely fast and when I always have something to do. Closest to being GCD-capped as it can. A 1-second global cooldown is also something I really like because otherwise the extra .5 second really slows everything down a lot. The lower GCD of casters is something I'd consider but I have a slight preference for melee.
I just hate sitting there auto-attacking for any significant amount of time.
I hate Focus with a passion, so no hunter for me.
I don't mind pets.