The thing about cruises is that they do everything they can to keep you on the boat (gambling in their casino) or on their excursions (for which they usually charge extra) or in the tourist trap markets near the docks. If you’re a sheep, do let them herd you whererever they want.
But if you really want to have a good time, get a good guidebook on the islands (I like Fodors) and read up on some of the more out of the way places on the islands you’ll be visiting. I’ll relate two stories from my 1992 cruise to the Bahamas.
The guidebook suggested that the best way to get around the island was to rent a scooter near the dock and explore at your own pace. When I asked one of the ship’s staff about this he strongly recommended against it, saying the scooters were unreliable and broke down a lot. When we got off the ship, I asked the very nice lady (Rose) in the Tourist office about that, and she said, If you have a problem, someone will stop and help you.
So we rented the scooters, went out, had a lovely time exploring the botanical gardens, beaches, and old ruins that no one else on the Big Red Boat got to see. And sure enough, at one point my scooter stopped working. I was poking around, trying to figure out what was wrong, and in less than five minutes a pickup truck with three teenage boys pulled up. Within a minute they reattached the spark plug wire under the seat and ran off before I could offer them a dollar or two for their help. Everyone we met in the Bahamas was friendly and charming.
(A warning about a real risk of the scooters: they drive on the left in the Bahamas, and it takes many Americans a while to get used to it. I didn’t have that problem, but accidents from driving on the wrong side of the road are not uncommon.)
Later, while most of the sheep…err, other passengers…were at the Captain’s Dinner (it was the second night of the cruise–they could have had the big dinner on our first night at sea, but no), my friend and I went into town to look for one of the restaurants we’d read about in the book. We found it, practically deserted, even though there were thousands of people eating dinner on the ships at the dock. We heard some music from around the back, and in a small back room found a fellow playing the piano. He welcomed us warmly. We had a seat and ordered a pleasant dinner of conch with beans and rice (a traditional native dish), and a little later he came over to our table. He said, Do you have a Bahamiam dollar? I pulled one out of my pocket, and he said, See that signature (i.e. of the treasurer of the Bahamas)? Pointing to a distinguished looking gentleman sitting with a few friends at one of the only other occupied tables, he said, That’s him.
We had a lovely time, thanks to not staying on the boat.
The only ship’s excursion I recommend you go on is to snorkel. Do not miss snorkeling. It’s wonderful.