I couldn't imagine any other way of fixing this than by implementing role requirements for queues and preventing people from swapping jobs inside a match. Probably a deathblow to FL as queue times would go through the roof.

Or I suppose they could totally overhaul pvp abilities and have healers "heal" in the same sense that tanks "tank". Unfortunately, it looks like they're going in the opposite direction with composition requirements by making physical dps the dedicated crystal damagers.