1st. idea: You can make on server more event like Capture the Flag, Domination, Mass Domination, Lucky Chests (player which opens more chaests wins), Hunting Grounds, Mutant, Zombies. can change a few maps of events.
2nd. idea: Make achivement like Moster killer (when killed 5000 mobs get reward), or adena maker (when have 500kk adena get reward), Treasture Chests opener, and so on.
:)
Regards
Dedix