I really wish more of the quests were viable. Quest priest is pretty fun but then stuff happens like queing into baudib on aggro druid when you're trying to meme and he BMs you.
The priest class early deathrattles are way too weak and the win condition doesn't seem to be different than normal control priest. Having 40 health is cool though.
I've made a questlock deck for dailies that does OK but the value you get from completing it is so terrible compared warrior or rogue...6/4 of stats a turn vs at least one 5/5 for rogue and a 2 mana 8dmg spell for warrior.
I have the druid quest but I never made a deck with it...just seems dumb. I mean you're only drawing one minion a turn after completing it and you're a druid so you'd have the mana to play them even they weren't free.
Have no ideas how they could be fixed just ranting. I wouldn't want the next expansion to make the un'goro quests OP.