I should have mentioned this in my original post:
The first shotgun I ever bought was a long barrel single shot 16. I bought it more or less as a favor to a neighbor when I lived in North Carolina. So I kind of backed into owning a 16. For a long, long time, it was my only gun of any type.
Its job was shooting crows, deer hunting, and home defense. Thus over the years I bought quite a range of birdshot, buckshot, and slugs. When a local GS would have a sale, I would always buy a box or two.
Fast forward to now:
Going through my inventory of 12 gauge, I was surprised by how much 16 gauge ammunition I have accumulated over the years. I'm never going to shoot all that up with a single shot. Besides, I like Mossberg's 500 shotguns so I thought I would look around to see if I could find one. Maybe this is just an excuse to buy another gun, make of it what you will.
Another point is that my inventory of 12 gauge buckshot is pretty meager. Just try to find some in local stores or on-line right now! So having a shorter barrel 16 gauge repeater may be prudent. Hopefully things will not get all that bad but ...
I may have to expand my pool of acceptable guns, but this is not an urgent requirement so I will stick with my preference at least for the short term.