So your choice of destination largely depends on your interests both related to diving and your wishes above the surface. Bonaire is in many charts of best diving locations in the world. The island almost seems dedicated to diving.
Curaçao is the largest of the three ABC islands (Aruba, Bonaire, Curacao) and has also very good diving, although not as extraordinary as Bonaire. Curacao though, has some cultural sites and also has some Golf courses (which aren’t there on Bonaire).
Aruba is the smallest island. It is focused on watersports, couples and family holidays. See the sections on each one of them to determine which one you like the most.
Whatever your choice, your vacation will be relaxing and sunny!