U.C.E a rideable relic?
I think so, yes. Hardly a day goes by where somebody does not mistake my 2012 Desert Storm for a MUCH older machine. That's the standard opening question, "What year is that?"
You are a bike guy, so you see things like the 02 sensor on the headpipe, and you realize the significance of a disc on the front wheel, but most people see the sprung tractor seat, the oval shaped tool box, see me kick start the machine to life, and think they are looking at a vintage machine.
Put it next to my 1999 CI Bullet and I wouldn't be surprised if most people are fooled by the more modern appearing seat, and choose the Bullet as the more recent machine.
As for the experience, I'd think I could make a strong case that the thing a UCE engine Royal Enfield is MOST like, is a CI engine Royal Enfield.
My 2012 does ride just a bit like a Honda. A Honda I remember very fondly, a 1968 CB450. The CB450 was arguably a bit more "modern feeling".