So, the mafia have 2 NK mechanisms, right? There's priming and hoping the detonator guy doesn't die, and then there's the hot potato.
Town controls the Mafia's nightly NK. We should determine, every day, who will die that night. Anyone who refuses to be the night kill is scum.
Remember, per the open setup, we're all just VTs with two identical, useless items. Like, two pieces of paper is crap. No town member should have objections to dying at night.
Basically, we can all decide/vote on who should be the NK. If they protest too much, SCUM and we lynch them. If they don't protest, but DON'T die, SCUM and we lynch them the next day (because that means mafia chose NOT to send the potato out, or that person received the potato and passed it).
Remember, the person holding the potato has the power to hold onto it and die. We choose who dies, mafia gives them the potato, they die. We are taking power away from mafia, controlling who we lose each night. We also force mafia into positions they don't like with the daily NK discussion.
They'll be caught during the day if they fight, caught at night if they don't die.
--CAVEAT: Mafia can no kill on purpose to frame a towny for not dying. That's still an awfully slow way to get your NKs through, so I'm not worried about it.