I have been playing Priest, and am currently playing with the following deck at level 14/15. I don't have a lot of time to play though, so I am not sure how high this can go.
I don't run Thoughtsteal or Holy Nova, as I have found those to lose a lot of tempo. The deck has performed pretty well against aggro, but I am trying to improve its control matchup. I don't have any legends yet myself, so this is pretty budget friendly.
Please let me know what you think.
2x Circle of Healing
2x Holy Smite
2x Mind Vision
2x Power Word: Shield
2x Northshire Cleric
2x Loot Hoarder
2x Wild Pyromancer
1x Shadow Word: Death
1x Earthen Ring Farseer
2x Injured Blademaster
2x Auchenai Soulpriest
2x Twilight Drake
2x Gadgetzan Auctioneer
2x Holy Fire
1x Mind Control
The basic idea of the deck is that the Priest has a lot of low cost spells, so he can make use of the Pyromancer and Auctioneer better than most.
Against aggro, I look for the Pyromancers and I make sure to play the cleric early, just as a body to slow down the rush. With the Pyromancer, a Holy Smite, and one other spell, you can destroy a 4 health creature and all 2 health creatures.
Against Control, I run PW:D for Rag, and Mind Control for Ysera mostly. I also put the Mind Visions in to play late versus control (before they play their legends, to hopefully get one of theirs).
I would say that the weak points of the deck are probably the 4 cards I am running against control (PW:D, Mind Control, and Mind Vision), and the Abomination. These 5 cards can probably be switched around without affecting the general feeling of the deck too much.
With this deck, I usually am able to draw a ton of cards, so I often have a lot of choices, which is pretty fun. Let me know what you think I can improve, or if you try the deck and like it.