We just got back from 11 days, first trip to Europe: Flew into Amsterdam 2 nights (loved Amsterdam, very scenic and lively city) took a train to Belgium (2 nights), train to Cologne (1 night, the cathedral was a must for me, English tours 3 PM, check online), rented a car in Cologne and drove to Burg Eltz & stayed on the Middle Rhine River area for 3 nights. Drove through Wurzburg (lunch stop) to Rothenburg odT (1 night). Drove the Romantic Road to Munich (2 nights), turned in the car and toured by foot/bus.
We only came upon one tasty brewery in Amsterdam (visited two of its locations - Brouwerij t'IJ) but plenty of tasty beer to try elsewhere in our travels. We liked the freedom that having a car offered us... taking trains and not knowing logistics of the language or operations is a bit arduous, but DB was slightly more helpful than others (there was actually an information office at the Munich train station, and people helping at our transfer location! Not the case in Belgium at all, or from what we saw in Amsterdam). However, once we got a car, my mother in law was worried we were dead because I no longer had time to send updates... too busy driving or helping to navigate, without the relaxing train rides (the trains were mostly only relaxing once seated, though. And even then, not always, depending on who was seated nearby... maybe some metalheads on their way to a music festival and apparently lacking headphones for their music, or a screaming, inconsolable baby)
I don't have much for suggestions in watches or motorcycles, but there were folks in line in Munich waiting for a SWATCH store to open. The Englischer Garten in Munich was really nice & scenic. We visited two biergartens, one lively with music, one relaxing on the "lake", and a pretty creek running through it. We took the bus to the center of the park. Beer is everywhere in Munich. Quite a number of museums are in Munich that might interest you, too. We stayed in Mercure Altstadt hotel in Munich... a convenient location, and though it was not Oktoberfest, it was still $50/night cheaper than Amsterdam (easily the most expensive hotel stay of our stops). Nice room, no view, good breakfast.
We could've easily added a day or more at each of our stops, besides maybe RodT (I think with not much else around, two nights may have been a bit much). Rothenburg was INCREDIBLY full of tourists, very family-oriented, when we arrived on a weekday at 3PM, through about dusk... it was nice at dusk to go walk the town wall when the families were all tucking into bed, and again to explore early morning, before 11 AM. Much of the town was bombed in WWII and rebuilt, so while the wall walk is cool (do the Night Watchman Tour, it's good) some of it is just a bit too "perfect", especially after visiting a city like Amsterdam that is tipping sideways, or Bacharach and other towns on the Rhine where all the old timber slopes this way or that. We loved the Hotel Goldener Hirsch hotel in RodT, a room with a view over the valley... but the AC was barely sufficient for a 95 degree day).
I didn't find the Wurzburg -> Munich Romantic Road anywhere near as romantic as the Rhine River area and all of the castles and villages (and the Boppard chair lift was cool). It was still nice, but since we were just driving through, it wasn't much. We did stop in Dinkelsbuhl, but it was really not as impressive after everything else we had seen. Our favorite parts of the trip were Amsterdam and the Rhine River (if you have any interest in delicious wine, Rhine Riesling is affordable and delicious... unlike ours). We stayed 1 night in Boppard and 2 nights in Bacharach (because the hotel I wanted in Bacharach was only available those 2 nights). We wished we had more than 2 nights in Amsterdam, for sure. Next time we will try to stay in a more affordable area (?) but our location in the Jordaan neighborhood was super convenient to everything we needed for a quick stay.