The problem, I think, is that this game has actually two types of players living together (three if we take the solo players), one group that enjoy and want to play with antagonists, the other that only want PVE. And there is a problem since some of the PVE players will drop the game before even try it.
Is an issue largely discussed through the forum, I think that the better solution is giving the player the chance to chose if they want to go PVE or PVP before going to matchmaking, and give much better rewards in an antagonist match, for raiders and antagonist, so you can encourage this mode.
I think that with this option you will have people that want only PVE happy, and better quality for the antagonist matches.