Since PvE (not only RP) is independant of WvW, why not simply let players select their favorite activities and group them based on that? There could be tags like "Casual RP", "Hardcore RP", "Casual", "Support for New player", "Events", "Leveling", "Social", "Dungeons", "Raids", etc; you check the ones you like and the game would try to match you with players with similar preferences when there's multiple maps it could zone you in. Communities are about like-minded people, so if the server can be smart when grouping people, that could mitigate the issue. And why not help people that enjoy the same thing play together? :)