There is no captains ball as it is not that kind of cruise. Island operate a very casual approach to cruising with no formal nights but it helps if you are reasonably smart for the Oasis and Steakhouse restaurants for which you pay extra. Pool towels are in your cabin (one per person) and you have to return them to your cabin each evening to get replacements. If you leave them lying around on the deck at the end of the day then you don't get fresh ones. We took a couple of our own which were handy and at least you know which ones are yours. We went with them around the Med and didn't think the excursions were too overpriced compared with other lines but in the Caribbean there are always local taxi drivers eager to take you on tours and they are invariably cheaper. Some have small people carriers so all 7 of you may even get into one of them at a push.
Hiya you will safe some money doing own trips but be extra carefull on return to ship to being early back as ship will not wait on you if taxi breaks down .its not nice thing to say but its better looking into this if you have not done caribbean cruise before .this is first time island doing these but enjoy cruise we allways do with them .