I'm a Canadain, and I would prefer the tropics to either Nova Scotia or Alaska. It really depends on what a person wants on a cruise, I want sun,clear blue water, warm air, palm trees, white sand, and icy cold drinks with little umbrella on them (
Those other routes are more, hot chocalates, warm sweaters, beautiful and (in Alaska) dramatic scenery, antiqueing in Nova Scotia.
It comes down to what do YOU want. There is no right or wrong.