I don't know about chopping and flipping, but I'd suggest a stem with a shorter extension, and perhaps restarting "saddle life" with a Brooks B17. Your flexibility is low and you can't for a little while at least get down to the tops or drops, so adjust the bike to a more upright position. Higher bar placement (Nitto Technomic stem or similar long quill), bar closer to you (shorter extension on stem), saddle better suited to less aero positioning (Brooks B17 or similar).

One would think clincher wheels are the strongest, but some tubular set ups are very durable even with a Clyde. An excellently built set of sew-up wheels is more durable than a loose-spoked set of clinchers. For some ideas, check the Clydesdale and Athena Forum here on BF.

If you have a local bike shop (LBS) with a very good wheelbuilder, you can have an old wheelset re-tensioned and trued along with bearing overhaul, and then it will be as good as it can be without total rebuild and replacement. You can buy new replacement spoked wheel-sets pretty cheap, but sometimes they are pretty cheap. If your old wheels are something pretty decent, it's worth it to maintain them.

For me it's been about 10 years since returning to riding (now 60 yo) and I still have a gut. But my flexibility is improving, lately due to doing yoga the past two years.

Some of your situation is fit, and some is fitness. If you have a local shop with a good fitter, I'd pay them to set you up on the bike in your current state. As your riding improves, your optimal fit will improve, so the bike will need re-adjusting periodically.