I started shooting certerfire pistols with my Granddad's surplus Remington Rand, and over more than a few years have handled and shot lots of 1911s belonging to other folks, in lots of different configurations. I don't care for the gun all that much in the stock configuration and would just as soon have a good Combat Magnum. But basic improvements do change the gun a lot, for me.
If I have to go bare-bones on a 1911, I want a reliable gun with decent barrel, modified GM-grip safety to accommodate a Commander hammer, and a good trigger. Bigger sights, a beavertail grip safety, and a checkered front strap are really nice, but beyond that, my wish list hits diminishing returns and I quit spending the money.
I have not shot one of the new, so-called mil-spec guns but I would think one wouldn't need to do a lot to have a pretty serviceable gun - maybe just a trigger job? I am not really interested in 1911s with long slides, compensators, optics, 20+ round extended magazines, etc., etc.