I played a game where the party set up was 1 healer, 1 tank, 3 dps. They had 6 DPS classes, 2 healing classes, 2 tank classes (though 1 could also queue as a DPS because they were hella squishy), so it was basically the same as this game.

The queues were 45 minutes anyway, especially for end-game content. They had 10-man raids and it took easily 1-2 hours to get in if you weren't pre-made.

DPS queues are always going to be bad in every MMO, because normally there's more DPS classes than there are tanks and healers. I don't think I've ever played an MMO with a queue system and the tank/heal/DPS set up that didn't have 15-60 minute wait times.