I am also in my mid seventies and also have arthritis in my hands and wrist.
For that reason I rarely shoot anymore centre fires like 9mm. I found great joy and satisfaction shooting rimfires.
My absolute favourite weight, accuracy, ergonomically wise is a Sig Sauer P226 Classic in 22 lr. Great trigger too, important for fingers that are arthritic. Another one I like is a Browning Buckmark standard URX, wrap around soft grips. From reading various posts I like to comment that at my age you don't care sweet tweet whether it was one of Pattons favourites or whether the FBI or navy seals carry it as their designated weapon. Shooting the famous, historic 45 does nothing for me but cause pain.No thanks. Ditto for the .40 or after a while the 9mm. For those in my age group who like to shoot a rimfire with a classic look, check out the Browning 1911-22, small and light weight.
Us old bucks, just like to get out there and shoot for fun and relaxation, being satisfied shooting and hitting our mark without feeling pain.
Also the great joy of not chasing your ejected brass. Rimfires are fun.