We talk and try to balance it.
In terms of this game: it's quirky to the point of risking being a themed game (the nrg's meant to balance things, but also has to judge Normalcy of making sure a Normal game fits within the guidelines expected of a Normal game, and this setup being heavily Doctor-centric risks skewing the line), but in my opinion, it's still passable as Normal, albeit a quirky Normal. (This, rather than the balance of the setup, though, is actually what I most want a second opinion on from Ircher, since I am aware that I am usually at the edge of the line in allowing things many reviewers would deem better for a theme game.)
In terms of balance, my gut reaction is slightly scumsided, but not strongly so. The scum have most of the information about the setup, knowing there's two town doctors and that there's a doctor enabler (they don't directly know the latter, but it is easily inferred by their enabler-finder), and the majority of the town's power is the two doctors who can be disabled, and might counterclaim each other, and might make the gunsmith suspicious of them due to mafia doctors being a common gunsmith false innocent (a fear which is in fact justified due to the mafia doctor).
These all give scum a very very very strong advantage.
But on the
other
hand, two town doctors if the scum don't kill the enabler allows for an infinite-heal loop and also gives incredibly strong kill-denial, as well as allowing for follow-the-cop in protecting the gunsmith and the rolecop. The rolecop in this game also is good at getting guilties and innocents, able to catch a mafia doctor who fails to claim that they are a doctor, able to clear the macho doctor enabler because scum are 99.99999% likely to not have a macho modifier, able to infer that the gunsmith is town from their odd/even synergy, and is able to infer that the enabler-finder is a scum role fairly easily (not to mention that the Informed goon is a guilty if the player hasn't claimed Informed since Informed town usually claim their info D1), if given even partial setup information.
However, these advantages rely on the town gaining and interpreting information correctly fairly early, which they are unlikely to do.
Basically, if the town play this well, it's hard for them to lose because scum have very little counterplay, but if the town doesn't play well and/or the scum do play well, then the scum can easily circumvent a vast majority of the town's power.
I'd call the game incredibly swingy off of that, and probably in the 55-57.5:42.5-45% scum:town range--not perfectly balanced, and very swingy, but passable as-is as a setup if you're okay with that.
But before giving this a /pass, I do want to hear from my secondary reviewer Ircher here for a second opinion on this.