We went on the Fascination for our honeymoon in January and had a great time. We went on a few more excursions then Pam did and had a great time on all of them. I didn't feel that the prices were overly high, I'm sure you could do better on your own but then you can waste half a day figuring out what to do and how to get there. We went on excursions at all the islands and our Sign and Sail total was under $500 for the two of us for everything all week that cost extra from the ship.
St. Thomas: Coral World and Coki beach are great, but we went shopping. I have been to St. Thomas several times.
St. Maarten: Golden Eagle Catamarn. This was so fun. It was worth the price. Not a trip if you get seasick easily, lots of people had that problem since it was pretty windy the day we went.
Dominica: Pools and Falls tour. Just as good as the more expensive, longer tour. This island is the poorest you will stop at and need to be prepared for it. Carnival doesn't suggest that you get off the ship if you don't take one of their tours and I would have to agree. Once you get out of the city it is beautiful, but it is intimidating at the port.
Martinique: We went shopping downtown. Make sure you take small bills. Most shops will take US dollars but some will give change in French francs. We took a cab downtown and then walked back to the boat, it is not that far once you know where you are going.
Barbados: We went on the Malibu Rum Factory Tour and on the Jolly Roger Cruise. They were both lots of fun in the sun. At Malibu you get a tour of the factory a free drink (large in size) and then a couple hours on their private beach. The jolly roger is a party boat where the rum punch is included in the price and gets stronger as the cruise goes on . I would agree that it is not the place for young kids as most people come off pretty drunk.
Have a great time, I know we did.