We took this same cruise 8 years ago with my wife's parents. It was such an amazing experience that we committed ourselves to do the same with our four kids and their spouses.
It did not disappoint. The Alruna staff treated our whole family like royalty. Their service and care were over the top great. I just can't imagine anyone doing better.
I was a little worried that we may have over-sold our kids on what to expect from Viking (this was the 5th cruise for my wife and me), but they exceeded the kid's expectations. Truly a wonderful experience and I'm pretty sure our kids will be back on a Viking ship at some point.
Once we figured out the crowd, we loved it. Stay off the beaten path and Amsterdam is great.