I was also hit while in the city today, it wasn't someone I'd attacked who did it. They lost due to poor luck on their part, however, I can see why that would be a major hinderance. So far as that bug goes, you could do things like your arenas while in one of the quest areas since noone else is in there with you.

Regarding the revenge issue, I logged on today and had to wait 20 minutes to play because I was in the middle of being revenge bombs, as I like to call it, by someone who wasn't happy that I beat them then they got stronger than me and won, then I got stronger than them and won and so on and so forth. It actually got very frustrating for me, and normally I don't get frustrated. I reminded myself its just a Beta and went and smoked a cigarette, but I can see this becoming a bigger issue when the first server is opened and more players interact on there than on here.