In Crystalline Conflict you actually have to think about all the actual job and game mechanics that don't really matter in mass pvp modes, and positioning matters ten times more as well. There is momentum, good target focus, how to break through enemy sustain, how to defend properly, how to soak damage for the team, etc. You also don't have allies to hide your mistakes behind. It's a lot more technical if you want to get good at the mode.