If you clear all servers i think you will lose some of the old players.
Here is my idea.
Leave Aurora or merge all servers. Create another - much harder server in which the characters will go after a certain criteria (for example 5 tributes). There is a need of new items, sets, monsters and quests.
I will also suggest top monsters (example - relics of kundun, asteroth) to spawn randomly on every map. There is nothing to go for in kanturu, lost tower and aida except for quests. These maps need to be made more interesting.
These are just my ideas.