Hawaii and Bonaire are VERY different dive destinations. Having done both, I can recommend both.
Hawaii diving is usually just a 2-tk am boat dive per day, you are back around lunchtime. Then you have topside activities, fancy restaurants, bars, nightlife, waterfalls, volcano tours, etc. Boat dives are always led by a DM, and prices are expensive. There is some shore diving in Hawaii. Kona has a manta night dive that is awesome. Maui diving has Molokini crater and Lanai caverns. Lots of fish, big and small, but the coral isn't as bright and colorful as in Caribbean.
Bonaire is the Shore Diving Capital of the Universe! People who go there tend to dive dive dive all day long. The reefs are feet away from the shore so you just walk into the water and go off on your own. There are boat dives but people don't always do them, or they only do 1 boat dive per day, then shore dive the rest. No fancy nightlife or crowds, only people on the island are divers or those working at resorts. Reefs are colorful and teeming with life. You won't see lots of big stuff - sharks, dolphins, etc. but you will see about every fish in the Caribbean Fish ID books.
Water temps in Hawaii in June are going to be 74-78 maybe, Bonaire water temps will around 80-82.