Update on my journey down the 1911 path:
I concluded that the sights on my Colt were a little off. I was getting tight groups, but usually consistently going to the right. So I bought a weird contraption, a universal sight adjuster:
It took a couple of trips to the range, but now my Colt is dead-on for 230 grain bullets at 800 - 850 fps.
I've also taken to handloading cast bullets for it. I first started with Magnus 230 grain LRN and 7.7 grains of AA#5. They were accurate, but resulting in some leading in the barrel near the bore. I am pretty sure that the problem is the bullets are too hard and weren't expanding sufficiently with my powder.
I'm about finished with that box of bullets and am trying Rimrock Bullets next, which are a little bit softer. The leading isn't a huge deal, it just adds a step in the cleaning process (with the trusty Chore-Boy method), but I'd prefer no leading at all.
I have also painted the front sight a bright neon green color, using some of my teenage daughter's fingernail polish.
The result, with the look-at-me front sight, the re-adjusted rear sight and the ducktail grip safety, is that it takes zero effort to keep all my shots inside a 3 inch circle at 12 yards. Since upgrading the Colt magazines with a better follower and stiffer spring, I've not had a misfeed.
For a defensive load, I've settled on the Federal Hydra Shok 230 grain jhp. I tend to put more faith in Marshall & Sanow than measurements in gelatin tests, and this round under their studies showed a 95% one shot stop rating. I don't take that as the final word, just an indicator of a round which might be more likely to be successful than others. I've fired a lot of the Hydra Shoks through the 1911, and had no feeding problems.
In case it isn't obvious, I remain smitten with this pistol. I'm not giving up my beloved wheelguns, but I am indeed a devoted fan of the 1911.