MyFreeCams.com has a list of things that are not allowed by models, it can be found at http://wiki.myfreecams.com/wiki/Rules_for_Models
It is important to either have this list modified to show current allowances or to have them enforced.
Many models at MyFreeCams are breaking these rule blatantly and it undermines those that do not.
Many models preform in public chat things that are against the rules.
It is important to uphold the rules you have put in place for the fairness of the workers.
I suggest a reporting system with warnings and suspensions with length according to offense and repeating offenses.