There is no way you can unite dev's of diff private servers to make 1 new together. Money runs the world. Why do you think there are so many countries? Same reason, money. No1 wants to share it. May be at the begging, when people are not so experienced with DB, they are willing to unite, but after years of hard working and learning they change their minds. Their ego grows, and they start acting like they are the gods of shaiya ( not all devs but most of them). And it the end they end up with a server very different from what shaiya is supposed to be.
Just check the pserver add. thread you wont be able to find a single server w/o 40%+ customization.
Pure pvp servers dont last long but no1 wants to waste months of farming for a server when it can simply be wiped out with single ddos. I believe people are willing to play on a farming server which takes about 10 days to get maxed. Any more than that is just waste of time. You will say people will get bored from non stop pvping. True, and here comes the server team's part. Most of the devs add new gears/lapises to make pvpers farm again, it works, once but after that people get sick of farming new gears. And every new item has to be better than the ones before, so the stat balance gets ruined. Instead of new gears, make more in game events. Mostly pvp is held on 1 map all day long ( populated server) and people get bored of this map. GMs should do other kind of pvp events, something different than just pvping in oasis or bridge in jungle. Something thats more challenging and requires some skills. Also dont forget pvp bosses. Sometimes the pvp for a boss ( killing/resetting) is funnier than just raid vs raid pvp.
Oh well i wasn't planing to write that much...

Anyway, if some1 is willing to make new server, keep this in mind. I believe many people will agree with me, mostly ep4 lovers.