Self-debarkation means you have to be able to take everything off with you unassisted. It is supposed to mean people with perhaps a garment bag and a roller carry-on, but it is often abused and I've seen people struggling with huge suitcases, slowing up the line in the process. This is the first group called to leave and it is also often the largest group.
It is always a good idea to have travel insurance, and I don't mean buying the cruise line policy. They usually offer less coverage and cost more than a better policy you can get on your own. You have to read travel insurance policies carefully. A policy won't necessarily pay for missing a flight just because you booked it at an airport several hours away from the port and the road trip took longer than you thought.
Another thing - I was looking at new member profiles and see you have a .ca e-mail address. So I assume you are a Canadian citizen but flying out of Plattsburgh?