First off, congratulations on still being an active rider at 75! Here's hoping you have another 25 years in the wind!
Have you checked out this thread:
http://www.cvoharley.com/smf/index.php?topic=86469.0;allI've given a fair amount of thought to trikes as well. I've even wondered what my WG2 would look like triked out cause I love this bike so much and can't imagine selling it but can imagine a day when I might have a problem handling it.
Fact of the matter is I'm just not crazy about the standard trike format from a looks/functionality standpoint. No problems with anyone that owns and rides one. Think they're great for keeping people in the wind and I believe we'll see more and more trikes on the road - that's great! Just not sure a trike is for me. I like the physics and looks of the Can Am better but don't like the limitations when it comes to options and motor choice. I know HD has looked at the 2 wheel front one back format but assume they can't figure out how to make it a Harley.
The whole sidecar concept still intrigues me tho. I saw a beautiful VRod with a sidecar in Sturgis last year. Simply a stunning rig! and the RG rig from the post link above has to be one of the nicest rigs of any kind I have ever seen!
Currently my wife rides her own bike but when I told her she could ride in the sidecar and hold one of our dogs, she said "sign me up". At some point, she is going to transition away from riding her own and the sidecar route just seems more acceptable to both of us. Perhaps it's because the bike still looks like a bike and the sidecar is an interesting conversation piece.
Whatever you decide, just be sure it includes riding in the open wind, however many wheels or whatever configuration that takes - enjoy the ride!