Cruise ships can be a fantastic way to travel. Be aware that, to stave off boredom, generally food is provided in all forms and overabundances. (My mother goes on a cruise at least every year. Yes, she is nearly eighty, but she would out-powerwalk you and swims everyday: last year she went on a walking tour of Tuscany.) Anyway, be warned that most people are older on a ship; some people retire and cruise around the world.
As for whether you'll like it, that depends on the ship, the culture of the crew and how much you are shelling out. Ships travel at night (there is little danger of seasickness out to sea, though November, if memory serves, is a stormy time in the Mediterranean: wasn't it late September when Xerxes's armada was dashed against the coast at Artemision?) and pull into port for the day, so you're best advised to plan your shoreleave to dash about and see everything.
Personally, I'd travel the Greek Isles by yacht (they are readily hired, including pilots) and spend a week or two just sailing around. But I like sailing.
I think it might be be the rainy season, too, in November.