At extreme ranges the scoped Trail Carbine is only missing slightly more now....I think. I'm not even sure with several hours of playing if it's the spread or me mucking up the shot. At the ranges my PC can render targets the head of a human sized target is completely covered by the crosshairs of the scoped Trail Carbine, so I go for torso shots only. Not missing much with those shots at current. The only really significant change was the AP cost losing one shot in VATS with 89 APs. The higher spread isn't enough to impact long ranged sniping. The lower ROF still allows for some crazy speed sniping when the player view kill cam kicks in.
You're settling for body shots but head shots are significantly more damaging, and much easier with the Sniper/Gobi. And again, the RoF of the Sniper/Gobi is higher than the Trail Carbine, so if you want speed sniping, they do just fine. You seem to be solely using/focusing overly on the power of the Trail Carbine instead of using a character built for crits/sniping with the Sniper/Gobi. It's easily comparable and better for certain tasks.
Odd question but at any point did you consider just re-chambering the Trail Carbine to .308 ammo? The gun is a dead ringer for a http://en.wikipedia.org/wiki/Marlin_Model_336 and that gun can fire the http://en.wikipedia.org/wiki/.308_Marlin_Express. Wouldn't be a perfect fit yet would get rid of the nagging issue of a pistol cartridge being on par with a high-end rifle round at long ranges.
The major difference between .308 ME and .308 Win. is that the former is rimmed, making it much easier to cycle in a lever-action. There is also the Browning BLR, but I didn't see the point. .357 Mag. and .44 Mag. are popular dual use rounds, so it made sense to have revolvers and LA rifles chambered in them. In real-world space, none of these rifles are firing at long range. The terminal ballistics of .44 Magnum rounds are generally superior to those of .308 Win. when used against fleshy targets at short to moderate range. We use .308 Win. in the real world because of its flat trajectory and high velocity, which is why some users have requested that .308 should have lower base damage and inherent DT bypass.