Two problems emerge as the world runs long enough for players to be come overly strong. Griefing becomes simply to easy. No town is truely safe unless they have Extreamly strong PvPers. This will drive the to its death as players work countless hours to build up thier town only to have the greedy selfish PvPers come along and destroy the town and loot whats worth takeing. After a few times of this the players that work hard at building towns will move on to a new game where they have a chance to keep things they make. This will become a bigger problem the longer the server runs as the new players will simply be pray for those that have had more time to become overly strong.
There needs to be a way that towns can deffend them selfs against these tactics with out haceing to be uber PVPers. Something like guard towers with ballistas that deffend the town walls from attack. Make the town have to pay a price per day or week in LP's for each tower they build. This way a town can guard against the bashers and snachers.
One other problem as the world runs longer and longer the land gets claimed and even though players have quit playing the claims remain. There needs to be more decay on inactive claims to keep the map open for active players to build and play on.