Never been to Puerto Rico, but as for the others... I agree w/ London on Labadee, jet skis are great fun, been there twice and did that both times. My wife didn't like it though because they go too fast for her. On our last visit there I went on the jet skis with my brother and enjoyed it much more because I got to go faster. My wife went with my son on the kayak thing, which she said was beautiful, touring the coastline, but strenuous. Also, the first time there we did a 1/2 day excursion to Malafini Beach, really loved that, just beautiful. Theres a beautiful beach there and they set up a bar (cash bar I think, we didn't drink that day). They set up chairs for you in the shade if you like and also provide beach floats and snorkel gear. I believe they might have 2 separate times to go to Malifini, one in the morning and one later on, go with the later run, who wants to sit on the beach if it's not warm out yet, right? That tour won't take up the whole day so you can do something else before or after.
The first time we went to Labadee we didn't realize that the place was so big, there are different spots on the peninsula that you can enjoy. I also reccommend the quiet, smaller beach on the far left end of the peninsula, great view of the ship from there. On St. Martin: There is a ferry ride to St. Barths that RC offers. I'd go with that. I've been to St. Martin 4 times now and don't like it. The best time we had on that island was Orient Beach. Last time we were in St. Martin we rented a car and drove around the whole island exploring different spots, though I don't advise this at all, it was somewhat stressful & hectic, getting lost and wondering if we were going to get back to the ship on time! Wish we could hav e taken that ferry to St. Barths instead. We were going to but they cancelled the ferry because of choppy sea conditions, drat! St. Thomas: Trunk Bay on St. John is my favorite. Catching a ferry from Charlotte Amalie is the easiest way to go. Royal Carribean offers this excursion, which is okay, except you don't get much time on the beach there, so next time I think we'll go on our own. Here's a link to a page which highlights our last cruise that did this same intinerary (excluding Puerto Rico) on the first week of a back to back cruise on the Mariner of the Seas.... http://www.myorlandoagent.com/PageMa...D=1546845&NF=1
What kind of bad experience did you have at St. Thomas?