I stopped playing...but warcraft takes my money now so I guess blizz still wins.
The game is too expensive. I spent 50 bucks on an expansion, and I get bored because I quickly stop being able to try new decks. If I kept playing every day then yeah I would get mostly a full set by the end of the expansion...but my interest just doesn't get there any more.
So either give more for spending money or make it easier to get cards. Maybe allow completing quests against solo adventures? At least then I can quickly bang out a quest and eventually get the cards.