The one "must not miss" is going to Maho Beach in St Maarten... do a search on youtube to see videos of the planes landing so close you feel like you can reach up and touch them! The cruise lines don't offer it as an excursion... probably a liability issue... but it's a quick $8 shuttle from the port - you won't have any problems finding a bus going out there.
Jan 2012 Carnival Conquest - 7 day
Oct 2012 Carnival Elation - 5 day
Jan 2013 Carnival Dream - 7 day
Oct 2013 Carnival Valor - 7 day
Booked on Ruby Princess April 27, 2014 Transatlantic 14 day
Booked on Carnival Freedom October 26, 2014 Western Caribbean 6 day
Booked on Holland America Westerdam April 11, 2015 Panama Canal 20 day