A way to keep players playing the game, would be to reward those that help others. The game already keeps track of what weekly events and what segments of raids the players have done. My suggestion is that when a player re-does NF or a raid with players that haven't done it, he gets rewarded a token that can be traded for rep at a new NPC in the tower (in the case of raids, one token per segment). This faction would work like the others, ranking would give a package that could contain shaders, emblems, weapons, armor, etc.