I have, actually, given it some thought. If you look at my first page it's one of the questions there, I believe.
Anyway, I figured it'd work like this: If the person playing the completely broken PC wants to continue playing as him, or her, then by all means I won't stop them. But if they don't, they become an NPC controlled by their 'owner', or me if I think I should. (Don't be alarmed, I'll try to keep my hands off and if I don't then I'll PM you about it.) They can use their slaves, or whatever, to bring in more people to hypnotize.
...I do not want people abusing this, however. Slaves cannot hypnotize others if they are NPCs, unless I control them. They can, however, do pretty much anything else, including watching other would-be slaves to make sure they follow their orders, and/or don't escape, or even chase them down if they run. I might change this rule later depending on how things go, but for now that's how it is. If one Hypnotiser gets, like, fifty slaves, then that's going to limit that, and if there aren't enough hypnotisers in the first place that would also change this. It depends.
Also: Good to have you on board, Matthew! n_n