Hello I am planning on traveling to Germany for three weeks in November. I have an idea of a good three week loop through Germany. I plan on flying into Berlin and out of Frankfurt. I also plan on buying a German Railpass for my travels. I have been to Europe two times before the last couple of years but I plan on being gone longer this time. I also should state that I am legally blind so driving is not an option for me. I plan on starting in Berlin and staying there for seven days and nights. That should give me plenty of time to explore the city center using public transit and have a couple of day trips. After that I plan on taking the night train for about nine hours to Munich. I will spend six nights there and again plan to explore the city using public transit and have a few day trips. After that I think I would like to spend two nights in Baden-Baden to enjoy the spa and local atmosphere. After that I would like to spend the last five nights in Frankfurt to explore the city maybe take a day trip to the Rhine area. Is this something feasible in Germany using public transit options?
"Is this something feasible in Germany using public transit options?" It's totally feasible. And, you can probably do it for less without a rail pass. "Berlin, Munich, Baden, Frankurt - you have plenty of time. If you come out to the Littleton Aspen Grove shopping center a week from Saturday (19th), there are plenty of us who will be happy to help.
Just be aware that in November, the weather over here is usually gray and overcast with limited visibility. This won't have much of an impact in the cities, but you won't see the postcard views of the countryside (on top of your already restricted vision). Also, there may be other spa resorts that would better fit your intinerary than Baden-Baden, which is a little far from your other destinations. Bad Dürkheim sits much closer to the Rhine gorge, and its just as well know for its wine as its spas. Bad Kreuznach is even closer. There's probably some around Munich as well.
Wiesbaden and Bad Homburg also have very luxurious, famous old spas to visit too. Not sure when you will be here in Nov. but many of the Christmas Markets begin that last week of Nov. So, visiting those might make up for the grey skies and early darkness that define Germany in Nov.