I don't see how level sync is needed in this game. The current system allows for plenty room to party with your friends. A 45 can group with 30s and get the 30s nice sp while still netting 80~ a kill for himself. It's not the fastest SP possible, but it is reasonable. If your being held back from pting with your friends because maximizing SP income is priority, that's your fault not the game's. XI on the other hand, you could be partying and someone would lvl up to the magically level where mobs start to check "tough" maybe "very tough" and if you dont move zones or replace everyone's xp is immediately ruined, that's why THAT game needed level sync.