Hearthpwn

The main problem in Standard is the abundance of strong standalone class cards. Altruis the Outcast is an obvious example. Being able to play a 4/2 minion for 4 mana that clears the board AND hits face WHILE playing tempo oriented cards is simply too much. If Flamestrike also dealt 4 dmg face, it would be too strong because of how burst oriented mage is. Altruis can be thought of as getting a free Flamestrike that also damages the opponent. The obvious difference between the two cards is the card cost, Altruis requires multiple cards to be played in a turn. Here comes the other issue; Demon Hunter has LOTS of efficient card generation and draw. Because you both clear the enemy side of the board, develop your own minions AND go face with 1 card, the opponent now has to clear to board AND heal to not die. By nerfing Altruis the Outcast to only damage enemy minions, the opponent can salvage the game by clearing the board and not die to burst so easily.

A similar problem of swiss army knife cards is Warglaives of Azzinoth. It simply allows you too much tempo swing in one turn. Against other tempo decks, you can kill multiple minions AND push face damage for a massive tempo swing with no setup. Against control decks on turn 6 you can fully clear a Khartut Defender, go face for 4 damage while keeping 1 durability. For 5 mana you have the ability to deal 12 damage in one turn split among minions as you please, for 6 mana you get 16 damage. With how strong the weapon is on it's own, and in addition the massive synergy with the +attack cards and powers, removing 1 durability from it seems like a fair nerf. 

Now over to wild Demon Hunter. You would think Demon Hunter would have a tough time in a format where it has so few class cards compared to the other 9 classes right? Nope, even with a very suboptimal deck you can very comfortably reach wild legend. This is thanks to Baku the Mooneater. Simply by making an odd card only decklist with the strong odd class cards, you can dominate the wild scene. The upgraded hero power from Baku is so insanely strong compared to any other odd/even deck from other classes. For odd paladin for example, you pay 2 mana to get 2 1/1 recruits, which is twice as good as your regular hero power. This is already pretty good, but what if it was possible to combine Baku the Mooneater with Genn Greymane? Spending 1 mana for 2 1/1 recruits would be absolutely insane and overpowered. Well, this is essentially what happens when you create an odd Demon Hunter deck, instead of making your hero power twice as good, it becomes essentially (not quite) four times as good. Odd Demon Hunters now have the even Hunter hero power that can also kill most 1 and 2 drops in the game, AND synergizes with 1/3 of your deck (most notably Warglaives). The damage taken from using the hero power is usually irrelevant in a tempo game, especially with cards like Aldrachi Warblades. My proposed nerf is simply removing Baku the Mooneaters interaction with the Demon Hunter hero power, which is in line with what happens with Genn Greymane. I simply don't think it is possible for Baku interact fairly with a 1 mana hero power.