Cayman. We loved Palm Heights and there are not many kids, but it is very expensive. Have also liked the Kimpton.

Panama
Costa Rica
Out Islands of Bahamas like Exuma for water sports and bone fishing
St John
Island hopping in the BVI
Belize for jungle and island

We loved Bonaire - very outdoorsy, easy to get around, snorkel almost anywhere, great park, some good food options. Thought Grand Cayman was over developed in comparison - feels a lot like Florida (and more small kids). USVI (esp St John) is lovely but maybe too small. Have you looked at Costa Rica? I haven't been but heard so many wonderful things about it.

Aruba or a club med

Colombia

We had a great time with our 18 and 19 year olds in Grand Cayman. We stayed at Morritt's on the East End. We did the jet ski tour with Fat Fish, the snorkel trip with White Sands, a day lounging at Rum Point, the botanical gardens, and the parrot rescue place. We also had lots of fun competing in the volleyball/cornhole/pickleball/minigolf/etc tournaments.

Grand Cayman

Where have you been in the Caribbean with your college age kids that they have enjoyed? Looking for recommendations for hotel/resort/activities. Our kids are active and love to snorkel, hike, jet ski and do any unique experiences where you could see wildlife - in the jungle or in the ocean. Would prefer a place that is not overwhelmed with younger families. Thank you!