Premade decks may be offered, but definitely not the best ones Blizz can think of or the best from last time if a repeat brawl. Already too quickly things degenerate to cookie cutter decks, just recall the "use three cards brawl" meta it was overwhelmingly Patches druid, followed by fireball spam mage, with some overload shaman and pogo rogues sprinkled in. That was 99% of the meta. We don't need more of that we need less. Ideally you could fix that with better matchmaking but we know that won't happen.
well if you don't give the players good decks, they'll get frustrated that they can't get 1 win. And in the pick 3, each of those decks had a counter. If the problem is not enough variety of decks, then they should ban or change problematic cards for that brawl.
It seems that with every tavern brawl we have people either upset that it's another rAnDoM brawl or when it's a brawl where you build your own deck, people are upset that they can't build a viable deck because the good cards are so niche normally.
So i think tavern brawls where you build your own decks should have a prebuilt option for each class that you can play even if you don't own the cards in the prebuilt deck. If it's a repeat brawl, they can have the prebuilt decks be whatever was effective last time
Also, i'd like to pitch some tavern brawl ideas:
Dead Man's Hand brawl; You build a deck of 10 cards with no duplicates, and at the end of your turn, each turn, you shuffle a copy of your hand into your deck
Limitless brawl; you build a deck of 30 cards, but you can have up to 4 copies of any card (including legendaries)
Couples brawl; whenever you play a minion, summon a copy of it. Whenever you play a spell, play another copy of it (targeting the same thing). Whenever you play a weapon, double its attack.
What would you like to see changed about tavern brawl, and what tavern brawls would you like to see?