Nice, very nice, collection, Bob. Some first rate M-21's there.
I'm at a bit of a loss as to the meaning of your note. The handling profiles I quoted are pure fact and express no judgment/subjective opinion at all. They contain the same sort of information as does a set of stock fitting dimensions. I think most of the folk on this board would look askance at anyone opining that a 14" LOP is the ideal and it is the duty of the shooter to adapt to the stock. Likewise, an opinion of 6 1/2# being the ideal weight would require an explanation of for who, for what, where and when. Do note that I refrained from expression of any opinion.
The above said, I am going to express an opinion. In my safe resides a M-21 Skeet model with handling as follows: 12 bore, 26" bbls w/ beavertail, 15 3/4 LOP w/ pistol grip, 8# 1oz, 3 1/4" balance to trigger, 1.85 unmounted, 8.23 mounted, and 10.32 compactness. In my opinion, it is a wicked good skeet gun. Here is why. I am 6' 2", 220#, slow muscle twitch, above average strength. and good endurance. Therefore, the 8# heft is OK for repeated lifts to shoulder. The 3 1/4" balance puts a higher % of the weight in my trigger hand and leaves my front hand with a lower % of effort to lift and a higher % for swing. The 1.85 (just slower than a Ruger Red Label 28 bore at 1.70) unmounted is plenty fast for low gun style skeet and sporting clays. The 8.23 mounted is sufficiently stable to generally overcome my tendency to relax at trigger pull and not follow through. The foregoing is an opinion of/for me and is not intended to suggest what may suit anyone else. However, I do hope some of you all try this at home.

Qusetions? (I know how to spell, but, maybe, not tyep)
DDA