PG shotguns..,yeah, I’m onboard with that. Never thought they were good for much other than “cool” factor range toys,
AK's—fair observation. The only ones I have are a Hungarian FEG SA58’s; one underfolder, one thumbhole. I’m leery of recent production.
Revolvers...yeah, a 4” K or L is perfectly acceptable...but a 2.5 or 3” on the same frame would work, too. I wouldn't recommend a J-frame to a new shooter, though...maybe a 3” with a full grip would work.