Not really good rewards, but something to add on top of what is there. I don't play arena to be honest, I do my dailies and some ranked, but since the Tavern Brawl has little to do with skill and deck construction, it should be a fun mode that rewards equal or similar to other modes. Granted if they scaled rewards to the number of wins, it would be a less punishing version of arena. But maybe that is what it should be, especially for new players.