The suggestions would be great, if I were building a mafia game. But as I've said, I'm building a game like Kings of Chaos, here's why the suggestions in this thread would not work.
There is no levelling system, users are ranked based on their average power for each statistic (Attack, Defence, Covert etc...).
There is only a set list of weapons you can buy, they are available to all members and the costs scale nicely with the games inflation. Weapons require the right amount of units to use them.
NPCs are not in the game.
Missions are only used as a tutorial feature.
Adding a level cap where users cannot retaliate against users with a lower level would be disastrous and cause a lot of issues
If you don't have a clue what I'm talking about, check out these similar games, where they've died because of the power creep our team is trying to combat (all of the games started at around the same amount of resources, look at the difference between the oldest and newest); Dune Wars (oldest), SGU Wars, Supreme Wars (in beta).