We've been to Europe several times in the past for the Christmas Markets and have plans to go this year.

Based on what we could get via FF/CC miles/points we will be arriving in Munich and leaving from Paris. We've been to Munich several times before and enjoy it. Paris isn't my cup of tea. Didn't have any rudeness but it just isn't a place for me.

Right now we plan to stay 2-3 nights in Munich, 3 nights in Stuttgart, 3 nights in Strasburg (France), and finish up near the airport in Paris for a night.
Some of the nearby cities we may try to vist include Ulm, Augsburg, Colmar (France), Esslingen, Regensburg and Freiburg im Breisgau. Most likely only hitting a few of them.
From photos I really like Freiburg im Breisgau and Esslingen.
Ideally places that are 1 hr or less train ride from our bases.

Anyone been to any of them and have any opinions on them?

And yeah, we've done Rothenburg many times as well as Salzburg and Vienna. Most of the places I lived above, except for Munich we have not been to previously. We have a friend who lives a bit NE of Munich. Unfortunately our last get together ended abruptly when I begin to feel bad and ended up with either food poisoning or some nasty 12 hrs of sickness bug. Hopefully that won't happen again otherwise this will be my last trip outside of the US.

We've also done other places such as Cologne, Nurenburg, and Heidelburg.

Thanks
Rich