I'm thinking of a San Andres type of Minecraft.I mean we should have police,mafia or robbers,cooks,miners,executives,wood cutters,gardeners,hunters;A stock market where everyone sell their goods (e.g: miner gets 25% of what he collects,and he gets at the end of the day/week 10 golden ingots...he sells them for food or TNT to a cop or farmer so he can be more productive.Of course we should make an arena(colloseum type where everyone on the server could participate just for fun and entertainment).The government should be the admins.They own the public buildings and sell houses for money that gets updated on the site.What I'm trying to explain is that you should make a radiar type of city:The Government Building and The Bank + a fountain and a parc in the middle,cheap buildings with apartments in the back(the price of the buildings gets higher as they get smaller and more luxuriant).
Then you get out of the city where farmers,hunters and miners go to work(they don't have to live outside the city,they can just have their own teleportation machine that acts like a car(only they can use it)).
At last,you should make everything available on your site:when someone buys a house,you can see it's owned by Mr.X .If someone's a cop,you should be able to see on a map(on the site) where he lives and how good he is as a cop.If someone isn't good enough for a job,he gets fired or gets demoted(does not apply to simple jobs such as farming or hunting).
About the jobs,you should make a video about how to get money,how to be the best at farming for example.
The Factions type is quite entertaining,but I think if we can add more ideas to mine,we will have a great MC server.Just my opinion