There is no convenient leave option for when a pvp queue pops up. This leads to people taking up a spot for the entire 60 seconds. This problem is compounded when 4-5+ people let the queue run the entire 60 seconds.
Fix: Replace the "Hide" button with a "Re-queue" option. Also add a "Leave" button so people can leave the queue. Make sure the buttons have prompts that double check if they want to use them. It would be infuriating to accidentally leave a queue when the rest of your team goes in.
When you join a pvp instance you stay queued for other ones even though you can't join them if they pop up. If you get a queue pop while in PvP , you hold that spot for the full 60 seconds. Worst case, there aren't enough replacements queued up on their faction for that instance to fill the team so their team is outnumbered for 5-15 minutes while waiting for another to finish and for those people to requeue.
Fix: When someone joins a pvp instance make them leave all their queues.
There is no staging area. In all MMO's with instanced pvp that i have played have an area where people zone into and wait 30-60 seconds for other people to zone in before the game starts. At least give the team a chance to have some more people enter the instance. Starting a pvp match as soon as one person zones in is a problem.
Fix: Make the match start 30-60 seconds after 1 player has zoned in