Watching one of the Wednesday night gun shows on The Sportsman's channel 722. Can't remember the company name now, but you would send your slide to them and they would fit their barrel to your slide. They mentioned they build their barrel just a few thousandths over spec and then measure and finish their new barrel to your slide in all the places you list above.There are many areas of tolerance on a 1911 that need attention if one wants accuracy;
On the barrel there are 5 areas that need proper fitting;
1 - Lower lugs and link, which force the barrel in the slide lugs.
2 - Barrel hood into breech face.. both width and length.
3 - Muzzle fit to barrel bushing.
4 - Barrel bushing fit to slide.
5 - Barrel lugs fit to slide lugs.
Slide to frame fit always helps as well. I've found the biggest bang for the buck for accuracy on a 1911 is the barrel bushing fit.
Having all the above tolerances checked and in spec is crucial for consistent lockup of the system for consistent accuracy...unfortunately some production 1911s fall short.