Castaway Cay is very well maintained although you could still see some of the results of Hurricane Sandy. Unfortunately, a front came through shortly after we arrived and most (if not all) of the optional activities had to be cancelled. The rain came in and the temperature dropped considerably. The Disney cast members continued on and tried to make the best of it.
There were a number of shore excursions available but I chose to wander around on my own. A local told me about the free trolley service that makes loops around the city (I wish Disney had mentioned this but I understand that cruise lines want you to take their tours). The trolleys are not sightseeing tours but are a great way to get an overview of the city and there are a number of stops so you can get off and investigate an area of interest. One of the trolley stops (number 14 as I remember) is right by the pier. I enjoyed my inexpensive tour around the city.