I am currently on the 10th (I think) day of my 15-day river tour, and water levels have not been an issue at all. Projections are that it will not be an issue, period. River cruise has gone great, as expected. Can't say enough good things about the various towns and cities we have visited, starting with Budapest, then through Austria and four stops in Germany.
A "sort-of-bad" thing about this experience is the unavoidable emphasis on food. You are only actually tied up for three or four hours of touring in the city, then sometimes you can scout around on your own for a while, but sometimes not. With this light schedule, we end up having a big, long breakfast, a big, long lunch, and a big, long dinner, usually lasting until 9pm or so. So although there is no intention of making it an "eating vacation," that is what seems to be happening.
A few observations about Germany past versus present.
Germans used to mock Americans because we are "all" fat. The Germans are quickly catching up. A decade ago, a fat German - particularly a woman - was fairly rare. Now it is almost as common as in the States.
Germans have largely given up smoking. Fifteen years ago, "everybody" smoked, now it is common but not prevalent. Most restaurants don't allow smoking indoors. Vaping may be a growth market here.
As always, there is a cornucopia of interesting cars in Germany, including a lot of American examples. It is not totally surprising to see a Mustang GT, or a Camaro on the German roads. Of course, German cars are most popular, with many more models than we see in the U.S. VW has vans, SUV's, and even a pickup truck that are not sold in the U.S.
The German experience of religion is quite interesting. NOBODY actually goes to church, but Germans willingly pay 8% of their income (for which a tax credit is given) to support the church that they belong to, but don't go to. They are proud of their magnificent churches and cathedrals, but look on them more or less as museums of local history.
Since WWII, they have spent BILLIONS to restore their historical churches, monasteries, cathedrals, and chapels...and the human race should thank them for it. They are a treasure.
On to Amsterdam. But not too quickly.