...Anyone remember Avidgamers??
It seems like this idea is quite similar, let me briefly break down what I remember from AG:
When you signed up you got posting rights for the main forum which included all 'help' forums, 'chat' forums, and advertising sections.
You could also create your own game from the ground up. Each user had the capability to register their own game as it's own separate website under the ag banner. So the url would read: www.avidgamers.com/myawesomenewgame
When you started a new site you could use the basic layout and just change the colors (or not...), it included a front page (with a log in for players who had been accepted) info pages (which could be set to public or members only), and forums (of which you could subdivide ad infinitum if you liked.)
Alternately, you could use 'advanced mode' as a GM and completely do everything from square 1. Your own formatting, forum design, anything you could code you could do. (It WAS as amazing as I'm describing, some of these games were absolutely jaw dropping).
There was a mechanism for rating players by level and then assigning those levels different permissions. So the GM had access to the back-room, but the rest of the players didn't. This level could only post in THIS forum, ect. Mainly this was used as a game mechanic, so you could create one character and join with him and be one level, then create a second character with a different level. How it was used depended largely on the GM.
Basically, within their own site the GM could do whatever they liked. They had total and complete control over who was accepted, what each player could see, where they could post, and if they kicked them out.
I don't know if you're looking at quite that level...but I still dream of AG 10 years later. (Aaaand I've dated myself, lol)