I dont think there will be longer queue time with separated queues.
It might even be shorter due to the fact that more ppl will be pvping with more balanced fights and the premade problem outta the way.
No one likes to be stomped all day, and if you can offer a better wz it will attact more ppl and therefore shorter queue times.
Its a win-win situation. Premades gets thier challange (if they really are up ot it?
) and PUGs get thier fun, balanced fights.