I'm doing this itinerary on Freedom later this year and here is what we have planned:
Grand Turk - Drinks, lunch & beach at Jack's Shack (Early port day, we depart at 2pm)
La Romana - Seavis Tours Saona Special Snorkeling Excursion
Curacao - Smallfield Adventures Sunset Cruise (Late port day, we depart at 11pm)
Aruba - Carnival excursion to De Palm Island (It's actually cheaper through Carnival than booking direct)
Let me know if you'd like more info or links on any of these.