Probably the easiest way for them to do this is to just let guilds have an RP toggle (ya know like more than half of the big MMORPGs out there already have.). If they did that it might even be better for the RP community. We'd be way more likely to find each other and we might even get less of the more obnoxious trolls because the servers would, at that point, be sorted by play style.
What this wouldn't solve is the issue of helping newbies find the community, but the Megaservers made that pretty difficult anyways.
It'd never happen but just being able to have an account or character toggle for RP/WvW/PvP/PvE would be lovely.
EDIT: Also as a primarily RPvE player who at one point DID attempt to RP in WvW it really isn't feasible. One or the other will suffer in quality and there really isn't any forgiveness in WvW like you can find from the AI for being slow and typing while you're playing.