Help me choose the retirement guitar

Best wishes! The special semihollow or the studio would be a nice fit in your PRS stable, especially for versatility. A fiore might be another option to consider. You mentioned you might want something to get on the heavier side of things. A custom 24 Floyd could do that but the bridge is divisive. The Tremonti up route tremolo singlecut could also bring the heavy without the hassle of the Floyd and the up route is unique to that model in the PRS lineup.
Really sorry to hear about your health issues. That hits close to home. My best impulsive advice is to think of a tone that excites you, and go for it. Hang in there!
started looking for HBII or Studio. I think I'm going to do something I thought I'd never do...go to another brand. Prices in Canada for PRS are just absurd. They were bad last year, and now even worse. They make my CS Fenders look like squires. Unless I find a shop that is willing to Neg like TGS used to before they closed, I'm probably done with PRS. Ordering from USA isn't sensible either with the dollar being so bad which sucks because I used to love dealing with WW.
I bought the new NF53 in black dog hair a couple months ago and am really enjoying it. I’ve been playing it more than my others. Looking at your list, I think it would be a great fit to your collection.

Prayers sent that you’ll be able to play for many years to come.