More deck slots. Sell them to me if you have to, I don't care. I will give you money Blizzard.

That Hearthstone Tracker was built into the game.

A free arena game mode where you could challenge friends, that didn't give any prizes.

A 72-card expansion that is 8 new class cards for each class, and nothing else. I would like that.

I think Blizzard bit off more than they can chew with Hearthstone in giving it 9 classes. A lot of CCGs stick with something like 4-5 mana colours (Magic, Solforge, etc.), because trying to design an equal amount of cards for each class/colour is so much more work once you have more of them. I still feel like because Hearthstone split the mechanics up into 9 different groupings, it kinda prescribes a little too much to the player how each class should be played. They all seem rather inflexible, aside from Warlock. This was probably intentional on Blizzard's part to make the game approachable, but when I think about the kind of goofy, weird decks I like making in Magic or Solforge, you kinda can't make anything like it in Hearthstone because you're kinda locked into a particular strategy with each class. Part of that is also because there aren't that many mechanically complicated cards that interact in weird ways.

So now that they've committed to 9 classes, I just want each class to have way more variety.

Some of them need kind of a major rework, too. The Warlock epic cards (Twisting Nether, Bane of Doom, and Pit Lord) are all kinda troublesome to use, and Felguard and Dread Infernal similarly get no love. The "demon" theme in general just gets ignored by a lot of people, aside from the 1-mana demons, and Doomguard. All the deathrattle is making Void Terror more appealing, though. Maybe Voidcaller will kind of fix the part where some of the demons never see play? I wish Warlock had more attractive cards, instead of everybody mainly using Warlock to draw a zillion cards in a deck mostly comprised of neutral minions.

Similarly, Rogue in theory is either all about weapons or all about comboing a bunch of cheap cards, but the weapon path just needs to be more viable. Warrior and Paladin both have ways to regain life/armour, so using the weapons on enemy minions isn't that risky. Rogue has zero life gain, so you have to be really careful about attacking too many minions with weapons, or you have to rely heavily on Blade Fury. I feel like they need to do something about that. Maybe give her a weapon where she is immune while attacking, like Gladiator's Longbow for the Hunter.