The White Pass Railway in Skagway is a must-see. You will hear about it often after your trip and will know exactly what people are talking about.
In Juneau we took a float plane to Taku Glacier Lodge. It was pricey, but an excellent flight and meal. Our friends took a helicopter ride to a glacier where they got to walk around on the glacier. They loved it.
There is just so much to do in Alaska that you just have to pick what appeals to you and then the next time you go you can try something else! And, believe me, once you have been there you will want to go again.
This is one cruise where a balcony is a must, if it will fit in your budget. There is endless beauty and you don't want to miss it.
Have fun planning!