My dream (2-3 years from now) is to head back to Germany for two months during the summer. Make that four years from now, when the Passion Play resumes in Oberammergau.
I'll rent an apartment near Traben-Trarbach, the town I lived in during my tour in Germany. Weekends will be for winefests and local excursions. Monday is always the best night for winefests: the tourists are gone, and the locals let down their hair.
Tues-Fri will be for trips outside the area: Amsterdam, Munich, Hamburg are a four hour drive away on the autobahn. I will also devote a few travels to Italy.
Sure, it will be expensive, but my youngest son will be freshly out of HS, and my grandson will be 10.
Do it! my older brother, having just left a job, his son gone off to college, and having some extra money saved, decided he was going to Germany. His wife couldn't leave work, so told him to have fun and go himself. He didn't speak German, and never travelled outside the USA (except to Mexican tourist resorts). He was nervous, but booked AirBNB in Berlin and other cities, and figured out the train schedule when there. He got so adventurous, he found his way to the tiny town in the former East Germany where some of our ancestors came from. Didn't find much about the family, but even met some nice people in a local pub who invited him for dinner the next evening. It was all a great success.
That works in Europe. Wouldn't necessarily try it in some other countries....