Hello and here is my idea:

there are a limited amount of factions in a server (let's say 5)
there are towns, 1rst town is the resource town, where everything is collected (ores, wood etc...)
the second town is the trading town where all the stuff is exchanged, bought and sold
the third town is the building town where all the houses and builds are situated
the fourth town is the event town, where all events and all the fun thing are
the fith town is the battle town where all the weapons, explosives and all the fights will be
whenever a player enters the server, he chooses a faction
then he has to decide with the faction leader in which town will he be sent to
the faction leader has to choose in what proportions he has to situate his members, whether it's war or money he wants

If he places alot of people in the resource town, his faction will get regularly alot of resources, if he places alot of them in the market town, his faction wins more money to spend on things, if he sends alot of them on the 3rd one, he wins a lot of building space for his faction. I he chooses the event town, his faction will have bonuses for the monthly tournaments in which lots of money and resources can be won
if he chooses the last town, his faction will get more battle boosts and weapons.

every month, the most prestigious faction wins an xp bonus for example.

off course every faction will not be allowed to have 2 players more than the other ones.

The bonuses will be calculated according to the proportions of players in each town.

a player will be able to change town once a month, but to change faction he must have both admin and faction leader's permission.

to counterbalance the faction leaders power (who will actually be a normal player) there will be a faction moderator.

the towns will be administrated by mayors who will be actually the server's admins.

please comment and give your ideas