I've been doing pretty good on my windwalker. Got a pretty easy 1900 on solo queue in a couple days. I havent tried blitz yet. But my healer friend has been PMing in game keeping me updated on his blitz losing streak, "0-4 today", "0-6", "0-8". He went from 2700 to 2400 in two days or something
He's pretty good, though. So I'm not sure what's going on. We always get an easy 2100 in 2s in a few days whenever we play.
I don't see too many shadow priests in solo queue. But thats 3v3 and it's uncoordinated as fuck with no voice. I just train them to the dirt on my windwalker. They are probably a lot better in rated bgs. They are probaly still even good in a real 3v3 where you run a good comp for them.
When you start gemming your gear don't make the mistake I did and buy the vicious bloodstone with honor. You'll need 2 or 3 to add gems to your gear and they sell them for honor but just buy them at the auction house. They are only like 5k gold each. Save your honor for the other thing(forget what its called) you combine with the vicious bloodstone. That thing can only be bought with honor. The guy that sells it will be next to the other pvp vendors in Dornogal.