Are you on MU? If not you should go there for your EPIC HUGE SECRET GAME. They really have the player base for the kind of game you're imagining. You'll likely need to host one standard game first because I don't think they allow people to host mashes without one standard game under their belt, but your game really needs like 30+ players to work like you're envisioning.
It also needs to be labeled as experimental, but they love that sort of stuff over there.
I've been asking for help from experienced hosts there and they want to completely dismantle it and want to take out so many of the roles I have in it.
Which hosts? ---
Moops? "I thought you were making up diseases? That's spontaneous dental hydroplosion."