People need to understand that Blizzard brings back these RNG brawls because they are popular among casuals, which is a much bigger part of the playerbase. They only have a fraction of the cards, so constructed brawls are no better than trying to progress out of rank 19 for them. Here at Hearthpwn, people have huge collections and it's an echo-chamber of "RNG Sucks!", but to the majority of the player base, random decks is their only way of leveling the playing field and are preferred.
On a second note, even when it's a RNG brawl, you can easily have a positive win rate. If you are good at arena, you should have no problem getting a 70% win rate in brawls like these (granted, this is a bit more RNG than your typical brawl). If you are bad at arena, you blame it on RNG.
2
Valanyr is a great addition for consistent buffs, let me know how it goes!
2
Unfortunately that doesn't actually work, they are copies of the minion (base type) with +3/+3 added on afterwards before shuffling. This means double buffing with dire-frenzy (or any other buff) doesn't work. The only thing that does work is adding a +1/+1 from keleseth.
2
I played a similar deck and very frequently you never draw dire frenzy, hunter is very short on good draw options in general so its the main reason.
3
You need to know the matchup a bit more, what to mulligan for etc. I think its one of the most overwhelming matches for the druid, so much life gain that their burst is useless. I routinely beat mages that get Aluneth turn 6. Hard mulligan for ramp, and if you already have it, board control cards like wrath, swipe and spellstone. Almost always nourish for mana first turn 4-5-6 (unless you have nothing to do for the next couple of turns.