A way to participate in PvP outside of regular Ballista based matches that would be allowed anywhere, but without interrupting others around you, would be the ideal way to go about this. They've already got half the idea done thanks notably to FoV NMs. Now all we need is the option to propose a duel with someone, or party vs party, etc.
Of course just straight slaughter is fun and all, but Ballista itself is more than just beating other people up. In fact, the main goal of Ballista is to score petras, not to kill people. Taking people out just made it much more interesting
I'm all for going and doing this myself. But the last couple times I set up Ballista, no one showed up. My server doesn't have the right player base for it. I like to picture Ballista as a sort of version of chess. I might not be the king on the board, but I'd at least be a bishop or a knight, whereas Caitsith's general population would make up the pawns, some that have already been captured. By this I don't imply that they are easy targets, but due to lack of experience and probably a case of ADD, can't stay motivated to learn anything, and ultimately lose interest very quickly.