I suggest the german Route Würzburg - Nuremberg. This could be combined with the Fulda-Würzburg route and you would have a very long route. Later, the route could be extended again via Ingolstadt to Munich. This is a very busy route with a lot of trains. The best way is with the new ICE 4. The route from Würzburg to Nuremberg via Schweinfurt and Bamberg is a good local route. This is one of the most beautiful routes in Bavaria, and there are also many freight trains. What do you think of this route?