Remember that we are talking about a card game here. RNG is inherently built into the game by the necessity of the card drawing process. If you want zero RNG in this game, uninstall the game now because that is literally impossible.
RNG also adds a ton to this game. We've heard Blizzard talk about "player stories". We watch all the Trolden videos (whether you want to admit it or not). Almost always the best moments about this game that you remember were the byproduct of some amount of RNG.
A card game inherently involves RNG, but there are ways to minimize it. Like I mentioned before, Duelyst lets you cycle one card per turn, which is
amazing for reducing your level of screwed-ness due to RNG. Did you get a 1-drop on turn 8? Cycle it out and try to get something better.
My issue with Hearthstone is that the developers
relish RNG mechanics that make the game less enjoyable. Warlock players released a collective groan when Spread of Madness was revealed. There's a reason Mad Bomber and Madder Bomber don't see play outside of Arena.
Edit: One of the great advancements Hearthstone has made over MtG is the gem system. Not having to worry that you will be flooded or starved for mana makes the game significantly more enjoyable. More thinking like that will move Hearthstone forward, not more RNGunk.
So Brann probably becomes a staple in Shaman come WOG I have to imagine.
Jeweled Scarab, Tuskarr Totemic, Master of Evolution, Fire Elemental just to name a few. Maybe it's time to actually give Rumbling Elemental some serious consideration, even if it's just as a one of.
IIRC, someone said that Brann won't make Master of Evolution proc twice.