Turks and Caicos is fantastic, and St. John's probably has the nicest beach I've ever been on. We stayed on St. Thomas and took a day trip over there. Also, as noted above, I absolutely loved Grand Cayman.
Actually in the process of booking something for our anniversary in a couple of months. DR, Costa Rica, and Belize are looking like the lead horses right now. I appreciate this thread, good job OP.