The Mage Questline still astounds me in how fucking awful it is. There is no mage deck that will exist in the next two years that has any reason to not run it. People say it's a combo deck but it's not. It's just a deck that happens to explode into combo because of a 1 mana card that they can always play on turn 1 and a 5 mana card later. It also can't run out of cards due to ignite. Fatiguing themselves was a legitimate weakness of having so much card draw in Mage (more spell mage). But no longer.
Xequecal
is right. Due to the existence of questlines the only truly viable decks will continue to be hyper aggro decks that can end games before quests are complete. With mage and warlock being the biggest culprits. Midrange exists in the form of handbuff or aggro rogue that can also end the game in a turn due to the battlemaster combined with stealth buff and conviction in rogue/paladin.
Only combo garrote rogue existing would be a huge improvement. That deck is actually hard to play and if you gaff your garrote turn you just die.
It annoys me because warts and all hearthstone is probably the best ultra-casual game I know of and its nice to just play a few games a day and call it good. Are there any other games like this I can go check out? Doesn't have to be a card game. But something casual that is totally comfortable to play while doing something else... on PC not phone please.