I'm all for Arena and Duel type PvP. The only type of PvP I'm not in favor of in this case is the toggle open world PvP if there is one mechanic present.

If you aren't flagged for PvP, then you attack someone who is, it would automatically flag you. That's fine for most games, but in these types, you could just have a group of friends flagged for PvP stand around a spawn area for an NM. Then if another group trying to camp as well misfires an ability and flag themselves for PvP, it's like vultures on a rat.

There would have to be careful balances to the rules of open world PvP if it were to be added.