Thanks to all respondents, but especially to Frank II. Your response was was what I was hoping for, a proposed sample itinerary from someone with experience in that part of the world.
We spend a month more or less each year in foreign travel. So far we have traveled mostly, as I mentioned, in the UK, France, Spain & Portugal. We are no longer so much "church and museum" tourists, although great cathedrals, history and great art still hold our interest. We mostly are interested in what different places feel like, trying to get a notion of how people live in them. We like to spend time enjoying life as a local would (more or less, obviously). We generally like to spend longer stays than my question would suggest, but we want to add a few new places to our album. Our trip this year is intended to be 4 to 5 weeks, and to include a couple of days in London, the more or less 10 day journey of my query, and a couple of weeks in Paris, with which we are quite familiar and I, especially, love.
We find train travel interesting, as well as efficient. Accounting for all the time to and from the airport, getting through security, and other attendant delays, train travel in Europe is not usually slower than flying for short to medium journeys and for me, less tiring. I sit and read and look out the window.
Again, thanks for all the responses.