Human paladin
I've never mained as a healer, so it'll give a nice change of pace this time 'playing wow'. Shamans don't appeal to me, druids do, but the races don't, and to me if I went priest it would just be less interesting (from a pvp perspective) with heals relative to paladin, and I view shadow as a 'thematically less interesting warlock'.
Now I do wish I could be horde, as I miss old Orgrimmar and much prefer horde theme over alliance, but I'll wind up leveling a Orc Warlock or Troll War eventually.