The Question(s): What is the overall trend that our current mafia games take? Do the roles have a variety of strategies, or are many of them quite linear? What do we want the answers to be, and are they currently so?
In my experience, this is how previous games work:
1. Civilians attempt to find someone they can all trust beyond a shadow of a doubt.
2. FG's try to prevent this, and kill anyone that attains this status.
3. If no one is found, or they are killed before they can do any good, the FG's win.
4a. If one is found and they are able to form a solid group, the civilians win.
4b. If the FG's can infiltrate this group, the game is more or less even.
As for roles, I have two categories: deep and shallow. The former means there are a number of strategies one can use that role. The latter is the opposite.
Deep Roles:
Liar - A very powerful vote modifier. Can remove two or four visible votes (the number in the thread) from a player.
Gambler - A player can choose to target themselves, or not. FG's don't want this ability, nor do they want anyone else to have it. However, daring FG's could use it if they chose.
Con Artist - Another very powerful vote modifier. A recent trend in early rounds is for close votes. The Con Artist is able to choose who lives and dies during this time. A choice that could either greatly help, or greatly hinder.
Vigilante/Virus - Again, vote modifier. Now that the player can also kill someone instantly, this player has many options.
Tradesman - Who and when you trade is critical. This skill can also be used to see if someone had been telling the truth about their secondary role, or to move a powerful ability to someone that needs it more.
Fallen Elf - Just as much luck based as it is skill. Can be used offensively or defensively.
Supreme Being - With knowledge of another player's role, this ability can be key in executing a plan.
Shallow Roles:
Village Idiot - This player wants to die as soon as possible.
Priest - The player targets himself, then either targets people at random, or targets key players. It just depends on how the game developed.
Witness - Just saves someone from being lynched.
Ghost - Also wants to die as soon as possible.
Immortal - You can't do much with this ability, it just protects you once. If an FG has it, they can target him to make that FG look innocent, but players are wary enough not to fully trust an immortal.
Vulture - The vote modifier can be strong late game, but by that time it loses any depth it could have had.
Armagio - Wants to use their ability in the first round. This provides the civilians with a trustable person.
Shrieker - Basically just used for hiding.
I'll stop there. Fellow mafia players, post your thoughts.