In order of what we liked both the island and hotel which we alway visit in Feb. YMMV for other times of year

St. Kitts by far the big winner really nice island and great diving. Try Turtle Bay for dinner ^ ^
Aruba- Second but still nice if you stay out of the tourist areas
Grand Cayman was just horrible. Bad staff, bad food, hard to get beach chairs. We can say nothing nice about it.

This year is Curacao. I agree with you about Hawaii, plus the water is much colder. We will never go there again. Ending a vacation with an all nighter is not the way to end it.