So here it is, my first idea.
As you maybe aware, if someone is banned for whatever reason, and you killed him; the system will take that kill back from you. If the system works like this, all the actions that the user has made should be canceled. That means if youre taking kills, you should also take the stats (if the banned user won - get the stats back to the looser, if he lost, take back the stats from the winner).
Simple. If youre taking one thing, you should cancel all the actions.
Banned users - removing kills = giving back stats
Stats its just a very narrow area what should be measured.
There are lots of other points, e.g. you lost not only stats, but all the benefits brought by having higher stats, e.g. hookers brings more cash; you can buy more buildings which will generate drug production. Also, the loss of stats has impact in going through levels, as it prevents you from ability to finish levels faster.
So, the idea is good, but I guess its to complicated to measure and rollback the real loss.
also we should have the credits we spend to get out of hospital/jail back
Funnily enough the guy who started the thread also got banned =D