I wouldn't go on a cruise. Not only are they horrific for the environment and plagued by slave labor, your crammed on crowded can in the middle of the ocean with a bunch of unsanitary morons and assholes. What exactly is the appeal here?
You also lose your native rights/laws in international waters. The security operating on the cruise ship might hold/be bound by starkly different ethical/lawful beliefs than you are accustomed to.