Give GMs more choice as to who plays in their games.
Unfortunately, this opens the door to unfair treatment to players. We all pay the same amount to attend the Con, and we all deserve equal access to games. If a Con attendee has serious issues with another attendee, you can bring this to the attention of the Con organizers, and we will do what we can. However, personal issues aren't really our problem to solve; that's something for you and the other person to work out between yourselves.