I'm afraid the rest of it becomes a comparison of blondes or redheads which won't get us anywhere. However, for every Parker 16 in the dimensions quoted by our friend from Texas, the same concern built dozens of 12s with 30" full x full choke barrels, that had 3" of drop in the stock, and weighed in excess of 7 3/4 lbs. They were by no means alone, here in the US, in that endeavor, either.
It is difficult to find a gun with those same dimensions built anywhere on the other side of the pond. Because that style of shotgun isn't all that useful.
Ted
Except for the sling swivel and and an open right choke I use a gun like just like that for a rainy day upland gun and a field trial gun. It works great in both those functions. I am fifty-nine and the 7-3/4 pounds is becoming too heavy for my creaky shoulders to carry, even on a sling, but it is very effective in those upland pursuits. A very appropriate configuration for someone that could only afford one quality gun. Say for ducks, geese, deer, rabbits, quail, pheasant, grouse, coyotes, and fox.
As far as 15 x 1-1/4 x 1-7/8 being the only acceptable dimensions for good shooting you, along with tens of thousand of others, have fallen prey to the marketing guys again; "Oh, you need ejectors to be effective," "Oh, you need a high stock to shoot well," "Have to have an over and under to shoot really well," "Oh! Need 32 inch barrels - like Digweed," "Have to have adjustable comb," "34 inch barrels are a must," "Need an adjustable rib," "Need adjustable barrel weights," "Need adjustable trigger pulls," ad infinitum. And those Darnes you (and I) hold in such high esteem were generally stocked in the same dimensions of the Parkers you are disparaging (Pre-WWII). And my AHE20 and BHE16 both have over 2-3/4" drop.
It seems I remember a fairly recent post about you having a Darne restocked to the currently fashionable high stock dimensions. Bet that Darne is the envy of all your trap shooting friends.
And I am not a wearer of suspenders. 185 pounds of rippling muscle does fine with a belt.