Alaska was our first cruise and it spoiled us forever! Alaska is so beautiful. There are wonderful things to do in every port.
The Amsterdam is a sister and co-flagship to the Rotterdam. They are lovely ships, and wear their flags proudly.
You can download HAL's shore excursion booklets from their website. Look through the offerings for the ports you'll visit. The problem will be deciding what you want to do, since you can't do it all in one trip.
Good luck, and enjoy your planning.