Although I'm a long time owner and user of 1911-type pistols, I also find the all-steel models to be a bit heavy after 8-18 hours.
I've tried all manner of good quality holsters and belts over the years, but it eventually still comes back around to the overall weight involved.
Also, in my case, I've found that slide/barrel length does have an influence, with longer slides making it a bit more difficult to wear a 5" model when seated in vehicles (and especially when getting in & out of them all day). I can't change the length of my torso, and different holster designs have only been able to mitigate this issue for me to a certain extent.
Many years ago I made the mistake of trading off an excellent lightweight Commander in favor of a steel (Combat) Commander. The advantage of the slightly shorter slide was offset by the weight of the all-steel gun.
A few years ago I picked up one of the SW1911SC 5" guns with the scandium aluminum alloy frames. Noticeably lighter to wear. Very slight increase in felt recoil. Nicely balanced compromise ... for me.
Of course, now that the company has revised their design and has released the new Enhanced Models (some of the changes being no firing pin safety, titanium firing pin & over-size extractors), I find I'm seriously considering ordering one of the scandium aluminum Commander length models ... which will sort of take me back to where I was in the early 70s when I owned that lightweight Commander. Go figure.
I really like shooting my all steel Colts (5", 4 14" & 3 1/2" models), but after years of having to carry a gun for hours at a time, I really like carrying the alloy framed guns for daily activities. Almost as much as carrying the even lighter plastic framed guns.
I suppose I could also offer that I've watched more folks have feeding & functioning issues with the smaller 1911-style guns than with the larger ones (4 1/4" - 5"). It's not uncommon to hear it said that the smaller models in the 1911 platform are probably less tolerant of shooter and ammunition issues.
I have, however, seen a handful of more recent production Colt Defenders offer their owners good functioning, and most of these folks weren't what you might call "frequent shooters", either. Maybe the instructor in my Colt Model O Pistol armorer class was right when he said that the Colt engineers had finally gotten their little guns running right. (I still don't care for the folded leaf/spring follower used in newer Colt provided magazines, myself, though, but that's just me.)