They need to stop forcing open world pvp. It needs to happen naturally. Give some reward system that is not based in gear and then give it a high risk vs reward.
I come from EQ2 where there was a fame system. Eventually PvP quests were added in which started this zerg fest, but before that, bodies dropped 1-3 tokens each encouranging solo play to garner more tokens. Along these same lines, there was a fame system. With fame, you could kill people 1 level above or below and equal ranks to gain fame. Fame brought titles and "respect". I never once look back on that old PvP and think it was a dumb idea.