Alternatively a DF option that ignores group composition, so you could just go immediately inside with the first bunch of people who want to go in, without waiting for there to be a certain balance of roles that may never happen. Same for pvp, just let everyone in who wants to play with a for-fun queue that just takes anyone, even if you end up with 4x dps and no healer or something. The game wants there to be 25% tank, 25% heal, 25% melee dps, 25% ranged dps. If say 60% of people who want to play pvp are ranged dps then a lot of people aren't allowed to play and will just be stuck in a queue till they give up and go away.