Balance in ATOM is a little funny tbh. Pistols/SMGs are overall complete garbage compared to Assault Rifles, they have worse dmg, range, and also similar or actually higher AP cost, which is hilarious.
But at the same time, fully upgraded custom revoler, which is basically still a piece of junk which can be crafted after an hour of playing, is more powerful than nearly any firearm you can get in the game, especially 10x better than any other pistol/SMG you can get.
It's the only gun with 2AP cost to shoot, which with perks giving you -1AP cost for pistols, means that you can shoot it for only 1 AP, and at the same time it has one of the highest DMG from all pistols, and requires the most easily available and cheapest bullets.
Overall, most AP requirements for firearms, seem completely random and illogical.
Also, fuck Fidel, the piece of shit cockblocker. I don't see why the devs thought it's a good idea to not give me an option to actually disagree with the dude and fuck whomever I want, but instead force me to be his little bitch, but whatever.
Still, the best Fallout since F2.