Why southern over northern as far as "the" thing to do?
One reason is the flight(s) home will be shorter. Ending a cruise up north and having to fly home from Anchorage is a long ending to a cruise. Flying up there on the front end will be tempered by the anticipation of the cruise. It is around 1400 miles from Seattle to Anchorage - or around 3.5 flight hours. Plus for me the flights home from Anchorage have terrible times - late night or early morning as in 1am. That means a long wait for a long flight.