Hey Nolesfan,
I, too, am a NOLES fan and live in the great town of Tally. I just got back from that cruise on Century. We only took excursions in St. Thomas. I would say that Puerto Rico was a huge let down. We felt very unsafe walking the streets. However, we did stop at this little restaurant called "Ambrosia". The food was "okay" but the service was great. I think the owner is American and was all over us with his service.
St. Thomas was the best. Depending on what your idea of fun is....definitely the Turtle Cove/Buck Island Snorkeling and Sailing Tour was THE BEST! We went in the afternoon on the Miss "K" sailboat with captain "Johnny". He was a young guy who lives on his little sailboat...but he was really down to earth and not uptight like some of the other captains. The water was amazing....you could see 80 feet down. We swam right with the sea turtles and saw many different types of tropical fish around the coral reefs. It was the highlight of the cruise.
Also in St. Thomas, we took the Coral World/Megans' Bay tour. Megan's Bay is gorgeous...but more so the little beach right next to Coral World is to die for. The water is so unbelievably clear that when the little waves break.....they are completely clear....no seafoam or anything. I took a picture of it and it's on my desktop much like the one that comes with the computer. Absolutely gorgeous. Some people we met simply took a taxi to Megan's Bay and stayed there half the day. Either way it's a must see.
We just went shopping in St. Maarten. BTW, you can bring back 6 liters of alcohol no matter where in your cruise you bought it. They say you have to buy it mainly from St. Thomas, but we found St. Maarten had really great prices. ($7.50 for a liter of Absolute Vodka and Bacardi Rum and about $8 for Bacardi Gold.) We aren't huge liquor fans, but at that price it was a steal (and it's great to have for guests). There will be many people hounding you about "free taxi's to their resorts and free lunches". BEWARE! This is a Timeshare touring deal. Unless you don't mind being at their mercy to see some of the island....we were not up with that. Many store owners/workers will practically drag you into their stores...especially if they are off the main street. We also heard that Orient Beach is somewhat nude (topless option) and we didn't do that either.
About Nassau, we were told it's best to take a taxi (actually like a bus) to Paradise Island (about $4pp/each way). The must see of course is the Atlantis hotel. If you go inside the hotel, they will tell you that it costs $20pp to have beach access. Our taxi driver told us that the government owns the beaches and there is a free access just past the Sheraton Hotel (you can't miss it). It is also $25 per person to get a tour of the underground aquarium. My husband was being cheap and I didn't get to see it, but there is quite a large aquarium just behind the restaurant of the hotel. Make sure you eat on the ship before you go out. (We priced food for lunch and just a sandwich was over $10....al a Cart!
In closing I would like to say that the worst part of the cruise was the short amount of time we had in each port. St. Thomas was okay, but we scheduled two excursions that day and didn't get to check out the shopping (my husband didn't mind). We had also brought a couple of bottles of our own wine. We brought lots of things they tell you not to take.....there wasn't any question of our luggage.
Have a great trip, sorry I wrote a novel and good luck.