As for it being done differently, I look at Iteru's role in that game. He had to win if he was the last person standing with his teammates dead [iirc]. The ideal town playstyle wouldn't work so well.
The playstyles would have to change, I tell you that.
Oh, INSTEAD of kills! If that is the case, then I can see this going either way. I trust the mafia will have the usual minority handle if this is implemented?
Regarding the town in this subset of mafia: since the root winning cause is always "when you've eliminated all unfriendly threats", then you'd have to give the town extra firepower to combat the converters. Lynch by day, have some vigilante out at night. Or even a neutral killer?
Wait. Both the innocents and mafia having equal numbers to start with gives the mafia a better chance of winning.