I'm very excited to see transmogrification come to wow. I just want to bring up a few points blizzard might want to look into for the new update.
My first concern would be teir 3 and asking kindly if it could be brought back into the game somehow because some of my friends and I love the look of the original teir three opposed to tier 7 IE. Teir 3 warlock.
The second concern is keeping a mainhand weapon to Main hand, where as certain weapons should stay main hand, but dual weilding some of the main hands in game would look very good with other armor sets.