This was our first river cruise. We were delighted by so many things, including the comfort and spaciousness of the rooms, the great food, the well-curated tours, the staff on board and more. I would note that the people in Prague were not nearly as helpful or friendly as those in Budapest, but that might be a country issue. You should know that the bus ride to Nuremburg is 4 hours long, our driver had no toilet paper and took us to a place requiring Czech crowns for the bathroom. We reported on how bad the trip was and they said they would fix it in the future.
But the water was low. We did a ship swap in Austria and it was seamless. Yes, some complained because of the few hours lost, but they more than made up by giving us some of the paid-for tours for free and adding a free option to Munich. That really delighted us and caused us to do things we had only thought about, but didn't want to pay for (like the opera in Vienna). We did pay for the boat ride to the Weltenburg Abbey and it was a wonderful trip.
We never found we needed anything that wasn't supplied. You may wish to bring a bandaid to cover up the light in the closet if it doesn't go off when you close the door, but that was the only unresolved problem. We found that the wine and beer with meals was enough for us and they offered some celebratory drinks at other times. On-ship entertainment was superb. I was busy every minute - we laughed about the books we brought and the idea of resting. You could, but then, you'd miss much.
Iit was great. I've been on ocean cruises. This was so much better. The room was small, but so well designed that we were completely comfortable. 4 large drawers, 2 shelves and a large closet meant all our gear was stowed and the suitcases fit nicely under the bed. The bathroom was the great surprise. The shower was large and comfortable. There was room to stow our supplies. Just an amazing use of space. We would book this room again in a heartbeat.
And we loved the large window and wouldn't upgrade because when you want to see things, you want to be upstairs where you get a 360 view.
Friendly, cozy place. We got a bus tour first and then went into the old city and were able to spend time on our own. It's very cute and you have to buy some lebkuchen. Best thing there. No other food - they feed you too well on the boat.