Not sure about this one. While it's nice to be able to queue with guilds and friends, keeping the queue to the 4 people party size ensures a level of randomness that levels the playing field a little bit.
Being able to go in with 8 people all on vent/mumble every single time is basically a 99% ensured victory, and a frustrating massacre for everyone on the other side.
While PUGing is not preferable, it should't be made completely not viable, and this would probably achieve exactly that.