Maybe you could make mafia meetings anonymous (like with MM) with a Bartender present - you could say the bar is too poorly lit or something. Keeps it simpler than introducing Driver-style mechanics.

Was thinking if he attends mafia meetings he could be used in conjunction with the Driver to create interesting situations. For example, Cop is visiting player A (random town role), Driver drives player A and player B (Bartender), Cop wakes up next day thinking player A intoxicated him. Also useful if there are other mafia members who are not currently attending the meetings. For example, if the Bartender is interrogated, he can intoxicate the Interrogator, saving himself and now allowing the Interrogator to come to mafia meetings. But I guess to limit the drunks it could be like the Strongman where he can only bartend once in the game or only one person who visits gets intoxicated.

So this must be a mafia which won't attend mafia meetings.
Drunk is a powerful role so some town visiting members could take advantage of this mafia role in their own favor.

Suggestions are welcomed and encouraged!