I hear you, Jet. I have 3 bikes that help me "categorize" my riding. An upright, turns on a thought, feels every bump racer with 25mm tires, a sport touring long-rider with 28mm tires, and a gonzo frankenbike with 32's for go-anywhere rain or shine. There's a feeling to riding the gonzo bike that is kid-like, informal, no expectations, spontaneous-- and just for fun. It's not a beater by any means (old Ultegra, DA, Suntour), and it does get ridden a lot. For basic health and fitness (emotional and otherwise), the riding you describe is spot on. And as we get up near 70, the understanding there is more than speed to cycling will probably keep us on the road.

"What's that, sonny, you've only seen friction shifters and steel bikes in old photographs? Well, here you see the stuff for reals. It still works-- and so do I. Eh? You hope to be riding like me when you're my age? Well, tuck in behind me on that plastic contraption of yours and lemme tell you about the philosophy of Jet.................."