The second and biggest problem will be when people start stacking teams. Getting stomped is no fun, which will cause people to stop queing. And after awhile doing the stomping is no fun.
I agree with you there. Seemingly there is no end to the amount of people who like to just run around showing that they are "superior". This happens in regular warzones too. There is no easy fix, and the only real solution I can see is to get a lot of people interested and queueing so that there would be only a few of those *****s and then you would only face them every now and again, while still being able to enjoy good competative games for the most part. For that reason I would LOVE cross server queueing, sad part would be that I wouldn't be able to play against some people who are actually awesome and recognizable for the most part anymore. I remember when it happened on WoW and I didn't recognize anyone, it made me sad. At the same time though it opened up the door and allowed for more people and when you don't recognize people you don't have others automatically giving up, so every game was interesting on HOW it was going to play out.