Workshop

There are too few mafia members at the beginning, and they might get crushed. If recruitment isn't successful within the first 2 days, the mafia might suffer a major setback.

Guardian
has a 50% chance to kill the attacker

I think this is unnecessary... it's very harsh with so many neutral roles in the town.

Thief
ND1 - learns the type of neutral role used by the target. If the target has multiple neutral roles, it steals the first one in the list.

Does this also steal the execution, or is it described differently? Overall, I don't have any major complaints. The roles are interesting, and I'd like to see their justification.