So a doctor, but with a 1-turn lag per heal?
Better than making everyone a 1-kill vig, but still not ideal. Still, Blacksmith could be interesting if used in combination with a Doc (i.e. Sheriff could reveal, get healed by Doc, get given a vest, and then use the vest later in the game once the Doc is dead).
Hm... I didn't like the Blacksmith idea at first, but the more I think about it, the better I think it is.
If the Gunsmith can only arm Civilians and Masons, he becomes a detector AND a Vig factory. Consider this:
I am Gunsmith. Nights 1, 2, and 3, I randomly try to arm various people. Night 1, I pick a Cit/Mason and manage to arm them. Nights 2 and 3, I can't arm the people (thus, not Citizen or Mason). One of those people reveals as Sheriff. The third is GF, but claims Citizen. Suddenly, the Gunsmith knows EXACTLY who the GF is, even with GF detection immunity on, and can tell the now-armed Citizens to kill him.
THUS:
You cannot exclude certain roles from being armed, without the Gunsmith becoming overpowered.
If you do not exclude certain roles, ANYONE can receive a weapon from the Gunsmith. Consider THIS:
Night 1, the Gunsmith arms a random person. It turns out to be a Blackmailer, who consequently Silences someone, and then kills someone else. Gunsmith has fucked over the town, and still has the chance to fuck up 2 more times by accidentally giving other Mafia guns. He could also give guns to Arsonists, Witches, Survivors, and other non-town roles (Jester with a gun?) and end up DESTROYING the town singlehandedly in a couple nights.
Thus, overpowered in town's favor if you exclude roles, overpowered in anti-town faction's favor if you don't exclude any.