If your port stop is Nassau and you like waterparks, head to Atlantis on Paradise Island. If you just want to hang out at the beach, forget the excursions. Grab a taxi and ask the driver to take you to a beach with public bathrooms (Cable Beach, Junkanoo Beach to name two). For a little extra, the taxi driver can first provide a tour of the island and then drop you off at the beach. If you just want to see the sights, book a private tour with Sandra Ferguson Taxi and Tours. I use this company for every visit to Nassau. Family owned, always on time, professional drivers, and immaculate air conditioned vehicles.