In St. Maarten, we did a private tour through Capt. Bob. He was great to work with and we love our guide Oliver. The main thing we did on the island that everyone loved was zip lining. They took us to Loterie Farm. They have 3 different courses set up. One for kids (~48" and up), an adult course and an extreme course. DH and DN (niece-14) did the adults course. My niece said it was the greatest thing ever. My mom enjoyed the outdoor lounge area and could see us occasionally on the course. I did a pass of the kids course with DD (4 y/o and very tall). Since my mom was close, the guides let DD hang with them while I went to the adults course. When a new group of kids came up, he let her go again for free.
In St. Thomas, DH and DN did Disney's sea trek helmet dive and enjoyed it. DN did the teen adventure on St. Thomas (Screamin' Eagle Jet Boat) and on CC (Teen Wild Side - kayak, snorkle and bike ride). The Screamin' Eagle also had a family ride and DD has already said she wants to do it next year.
We loved this itinerary and ship so much that we booked the same schedule next year so we could repeat it all.