i got lucky alot disenchanted all the useless cards and i'm pretty good at arena. brm has alot of cards that allow you to make good tier 2 decks, you obviously need brm for gp and thaurissan is helpful for alot of decks. tempo, zoo,demonlock, alot of the hybrid and face hunter decks, aggrodins, all get stronger with brm. as for dragons i really view those decks as tier 3 maybe tier 2 decks so i really dont play them anymore