If you have always loved the PvM aspect of RO, Payon Stories is the server for you. The server has modified the EXP table for almost every mob, which balances the HP and difficulty ratio to their exp, making many monsters much more viable as compared to old school RO. I personally love exploring the world and leveling at places regular servers would never travel to due to poor exp and drops. In addition to that, the server has occasional events and costumes to keep everyone busy.