Again, thank you all for your input. Truth be told, there's more to my decision-making process than discs vs rims. I can't deny some of this is plain old "want a new toy" syndrome, but there are some real issues motivating me, most of them age related. For starters, I'm more comfort oriented/discomfort averse than I was 20 years ago. Chip seal pavement is a real pain in sensitive several places with my BMC's head and seat tube angles, short chain stays, and short trail. Secondly, my left knee took some serious damage in a motorcycle accident many years ago, and I've now got some post traumatic arthritic changes flaring up. So gearing that offers lower ratio than my current 34-29 bottom combo would be welcome. That's even more of a consideration now that we live in an area with more interesting topography.
At least those are the talking points I'm using with my better half to get her buy in. And they seem to be working
So that's the story I'm sticking to even though I can't deny a certain fascination with new & shiny.