It depends on the level of activity you are planning on doing but what you described is probably what you will need.
The key to an Alaskan cruise is "layers". You may have 70F and sunshine or 50F and rain within one day. You will need to be able remove and add outwear that can be removed and stored in a backpack for your day trips.
Rain gear and ponchos work well for both warmth and to stay dry. It is also compact. An underlying fleece or wool sweatshirt is great and can be pulled off if needed.
Low ankle hiking boots or good all terrain hiking shoes such as Merrel's work great. You don't need to pack something for each day. You can re-wear things.
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