Can you post the Rules in graveyard? I can't access them through the web app (I don't seem to be able to log in). There's been a lot of variation on what don/mayor/police officer do.
Basically configuring balance in such a tiny game is REALLY hard. What I did when I ran a game last summer was give less total power, but without eliminating the powers from existence, e.g. there was a single charge that could be used as manipulate the press OR hire a hitman.
For a 16 player game (2 mafia no rogues), I gave the following powers:
1 conscription
1 manipulate the press / hire a hitman
1 frame a townsperson / plant evidence
2 set a traps (these were regenerable)
1 slaughter the weak
2 bring out the big guns
This was the ruleset:
https://docs.google.com/document/d/1mrA ... wg1k/edit# (I think the main items of interest are the existence of seer (relatively strong role), backup (weak role), no police officer, and a mayor that investigated every day).
Mafia proceeded to absolutely crush town, not even losing a single mafia and without town even knowing who a single one of them was by game end (but that was very player-determined, rather than power determined, IMO).
Mafia has more powers (not counting conscription) available in this game than in that game. So I think it's very likely that mafia have too many powers here. IDK about removing a kaboom (I'm hesitant to only give them one), but I think you should cut a Manipulate the Press and a Set a Trap (yes, non-regenerable makes them weaker, but in a game this size that probably doesn't change much about the power). If I were GMing, I would have given a single hitman/MtP charge that could be used for one or the other, but that's a non-trivial change from your rules and I'm not sure if you want to do it, especially because game has already started.
Also, sorry if I'm being too involved of a spectator here.