You could rent a car and do 3 to 5 hours if you hustled getting off on your own. I hear it takes two days to do it justice, but Im sure you could see enough on your own that it would be worth it. Have you been to one of those 3D movies? They are amazing, if its snowing it seems like its snowing on you, so to see the 3D movie there would have to be fun, though there are so many other things you will want to see.
If you have any interest in that type of thing Id go. Iv seen more than my share growing up, my Dad worked for NASA.
Post-cruise excursions usually include time to transport you to the airport. Excursions typically disembark first (or after VIPs). You reclaim your luggage and board a bus with you luggage beneath you. Check the excursion details as if you are going to book it and you should see the departure time. Of course you can check with the excursions desk on board to verify that you will have enough time.
A Bad Day At Sea [with power] Always Beats A Good Day At Work
Coral Princess - tour starts 5/31 in Fairbanks