lots of stuff there.
There are no glock type triggers in long arms, but how many Siglike triggers are there? Does lack of a feature in a longarm directly equate to that very feature being obsolete or otherwise undesirable in a defensive sidearm? If so, how many "safe=up, fire=down" safeties that you SHOULD ride like the 1911 are there in longarms? Many of the longarms that I'm familiar with have button style ones near the trigger. Others, on the right side.
I'm not as familiar with longarms as handguns, but if you have two distinct manuals of arms anyhow (location of safety does qualify), shouldn't you learn how to use them both as-is.
Further, longarms are frequently carried on slings, exposing the short, light trigger to twigs, gear, everything else. Handguns are carried in holsters, the good ones should absolutely protect the trigger from anything I can think of that would cause the weapon to discharge. If the handgun was worn with an exposed trigger, I'd say safety engaged would be a must. If the rifle was stored in a rigid container, with the possible need to bring it into action quickly, would it be prudent to have the safety on as well?
To me, longarms are more offensive in nature in the sense that you choose the time to attack. The one exception would probably be home defense, and despite the short, light trigger, my plan would be to grab weapon and disengage safety sooner, rather than wait to disengage the safety until the weapon breaks 45 degrees like so many train on the 1911.
To compare HANDGUNS, which are usually defensive in nature for all intents and purposes (why not use a longarm if it's premeditated?) to each other is also interesting. SAs are used by many, granted, but how about safetyless DA/DAOs like most serious revolvers, Sigs, Glocks, etc? "Accidental" discharges that are NOT related to negligence are basically a thing of the past, and any weapon weilded by a klutz or fool can be dangerous, regardless of safety...
I agree with KISS. Point and shoot is about as basic as you're going to get.
If training will teach you the difference between the safety on your 1911 and the one on your AR or SG, then it will also teach you the difference between your SIG, revolver or Glock and your AK or Rem 700.
btw, not sure where you come up with 10x the number of SAs on duty vs. Glocks. I think Yavapai Sherrif out here is the only agency I know close to me that issues 1911s. The city I live in allows officers to carry what they qual with, the vast majority are split between SIG and Glock, the remainder are all revolvers, HKs Berettas, 1911s, etc. Besides, the folks that KNOW and CHOOSE the 1911 are hardly using out of the box pieces, probably few cost under $1000. The fact that a $500ish pistol even closely compares should be a testament to its design. Some guys that KNOW and can choose, choose Glock for a reason that isn't simply because "it's what their students learn." I believe Jim Crillo is one of them, saying if he had to do it over, it would be a G21 on his hip. Blackwater is issuing G19s to their people as a sidearm to the M4, so there also must be something they've figured out in training.
I think the safety feature is more for longarms which, as I said, are frequently carried with open trigger guards. When the safety flies off, all hell breaks loose. If you have to make the bummer transition to a sidearm, I'd think you'd want it to be out and ready to go no matter how you grip it.
I'm not trying to make the case for Glocks in particular, it's just convenient because the frequent argument about them is that their lightER trigger than other DA/DAOs makes them a prime candidate for NDs relative to the others.