Ret is pretty easy but it’s been my main since I started. Guess I’m biased but I love the wings and just going ham. Plus the utility to get yourself out of trouble with bubble and BoP and WoG and LoH. I don’t know, I love it and I have a few alts but I always come back.
Plus I can tank if I want for friends. Healing, pass on that.
Destro Warlock easily. The current Ret Paladin build is pretty straightforward as well, although it can be a pain with prioritisation to avoid wasting Holy Power at times.
Fury Warrior probably isn’t too bad but it is a fast rotation, and Elemental Shaman is probably another decent choice if you run something other than Icefury/Master of Elements.
Frost DK is, but I fear BoS breaks their requirement for not having to set up scenarios to do good dps.