If you can get to Rothenburg On The Tauber for the first weekend in September there’s a medieval gathering of all the locals. Beer , sausages sauerkraut in a stunning town. Book early....
I did the Romantike Strasse a few years ago starting from Warzburg, I still have the routes I took if you want them. Rotherburg is a must see, when we arrived there was a number of USA college or school orchestra/bands playing in the main square which was great.
As others have said, the Romantic Strasse is a collection of "romantic" destinations - old walled towns etc.
We have stayed in Rothenburg a few times and last year we had a stop-over in Dinkelsbuehl, lovely small town - we stayed here:-
And if you get to Fussen and decide to visit Mad King Ludwig's castles then pre-book your tickets online otherwise you will queue for 90 minutes at the ticket office. DAMHIK!