It does seem obvious from the intro that there are both mafia and town in this game, and those are the only two factions. (Although a SK could exist.. I can't think of any in Shakespeare literature though... Titus Andronicus perhaps?) A 7/2 split for town/mafia seems to be the only split that makes sense, or 6/2/SK.
There are probably some pretty insane roles, though (I hope there are!) There could be a Puck character who causes characters to switch factions, or mistakenly target the wrong character at night, or some other form of puckish action. Or Macbeth, a traitor, could be a town-aligned member who switches to the other faction when certain conditions are met (Perhaps there is a King Duncan, upon whose death Macbeth becomes a mafia member? That'd be thematic!). There are endless possibilities for cool roles.
Anyway, the proposed soft deadline works for me. And thanks for the vote, Xeiron (not!)