Well, I've been thinking of hosting a mafia game for a while so I thought of various aspects and themes that might be the best. I thought about WW2 for a second and then thought "oh cool, it would be awesome if people could make treaties with other people and spice up the game", and then I thought about it some more. Essentially, I have a new concept that might work out just fine; Treaties.
You may PM <hosts> with "Day/Night X - Signing a treaty with <user>". If both you and <user> PM this message with <user> being the other side of the contract, you will complete your treaty <--- or somewhere in the lines of that. Basically, both sides need to agree and user a should send a message with user b in it and then the other way around. Basically, maybe the "treaty" can change with the mafia, but I personally thought of "you are not able to target <user> with any harmful ability (theif, hooker, kill, ect., but inspections, safeguards and revives ect. are allowed) and <user> will not conflict with your win condition". If the latter bit isn't enough to make treaties worthwhile, maybe an added benefit of a new combined power like... anything really. Like, if an inspector and a redirector unite, the ability can be something in the lines of hooker or something else completely new. As an alternative, it may simply bring both users an upgrade. As in, say the former mentioned inspector is a full inspector - then maybe his action will be upgraded as such: "Night X - send <user1> after <user2>", and then if someone can tell who targeted user2 that night the targeter would appear as user1 and not as the inspector. But if we do upgrades like this, maybe a limit of.. two treaties is adequete? Maybe even one? I'm not sure, so I'm hoping you guys can come up with some interesting stuff regarding this.