Your trip sounds ambitious. Although the distances from place to place are easily doable, you've selected a number of cities that require sufficient time to get beyond a tasting. I've been to all but Cologne and Dresden and suspect that each of the others would merit at least three to four days just to get you feet wet. The other stops on your itinerary are familiar and altogether you may need a month or more. Here are two hotel suggestions to help get you started:

Berlin: Hotel Art Nouveau http://www.hotelartnouveau.de Rothenburg (Romantic Road): Hotel Eisenhut

Per King Ludwig's Castle, a.k.a. Neuschwanstein: It's best seen as a drive by or perhaps under a full moon. The up close and personal tour was less interesting than the distant view.

Regards, Russell from Connecticut