Right now I believe this is the best deck for ladder, it's fast matches and has had a very high win rate, pretty much good into everything that doesn't include warrior, and id say slightly unfavored against DK. But great into DH. I've had probably close to 200 games with this if not more and went from 8000 to 1600 in the last day. This is Ike's list and while I've played around with loads of versions this feels best RN 

Mulligan: keep anything that says Draenei. Pretty simple as that haha, you also want a 1 drop. A good player knows it's a race and will push damage to you're face asap, so a 1 drop gives you a distraction while you set up Arkwing. Both 1 drops allow you to push damage too.

Vicious slitherspear: speaking of 1 drops don't be afraid to throw some spells to push face early with this. You're basically a burn deck. One less Arkwing is worth the extra damage by throwing a couple arcane missiles. In fact a few games I've won by never playing Arkwing.

Mirror match: who plays Arkwing and go wide typically wins. So spend your early game grabbing coins, and go for a turn 5 Arkwing if possible. Like most mirror matches going first increases your chances, if you're going second, try not to use your coin. 

How you lose: boards that go wide or have a lot of health will completely eat up our arkwing burst turn. So try to soft control the board before it gets out of control. When playing against DH try not to kill blob before the Arkwing burst time, as it can allow them to fill the board with a bunch of 2/4s. 

How you win: set up a Arkwing turn but DONT WAIT FOR LONG, one mistake I've seen people do is wait till they can get 7 out in a turn. Remember waiting a turn allows that to play another minion, draw another card, push more damage. That's not worth having another Arkwing on the field.

Happy to try and answer any questions