I am pretty sick of a few things about pvp.
1: people who beg for their cash back after they die in there. I know there is nothing you can do about it, however this trails off into a kind of different subject. Enforce the ignore list! I swear, if one more person spam trades me or spams my conversations with public chat after I ignore button them and it doesn't stop them from pestering me... Ugh. Perhaps there can be 2 stages of ignore: PM ignore and Full Ignore. Full ignore, you guessed it, ignores everything, while PM ignore, you guessed it, only ignores PM's. (sorry if its a little irrelevant but I am killing 2 birds with one stone, just deal with it.)
2: Spawn camping. I do it on accident sometimes (with the occasional malice intent on purpose too), and others do it to me on accident or intentionally. Make it so when you enter you can't be killed the second you walk in!
3: Sometimes in the sparring grounds and maybe GvG you can die then respawn and die again, but when you die again since you respawned outside of the sparring grounds you loose your cash! This glitch has caused SERIOUS problems. FIX IT.
4: In dangerous PVP, often you want to 1vs1 someone but there are others there and they slaughter you and your buddy and ruin the stake! No good for anyone if you ask me. There should be a duel arena kind of thing where you can set teams and who is in which team up to 10 people per team or so, and like GvG they could spar it out, cash prize included for whoever on the opposing team gets to it first.