For experienced divers, Id recommend against buying guided dives as a practice. Instead, select an accommodation that suits your need for luxury, (non-diving) services and cost. Then rent weights and buy an all-the-nitrox you can suck package from whomever is conveniently located to your hotel. Anybody with a drive-thru tank change would be tops on my list. Drop in on BonaireTalk.com and browse some of the threads on favorite dive sites. Make a list of the ones mentioned most regularly.
Buy a copy of Susan Porters Bonaire Shore Diving Made Easy. Curiously, theyre available cheaper on the island than online. Burn photocopies of the pages about those sites youre interested in diving based on your Bonaire Talk research. Conventional wisdom is not to leave anything in the truck when youre diving that youd miss if it was stolen. Having photocopies lets you carry directions and descriptions from the guide book when you go to dive without risking losing the book itself.
So do your homework, plan your own dives, be prepared to search out the dive sites yourself (nothing short of GPS coordinates could make it easier), then go dive you tooches off, where you want, when you want.
For a different look at the island, dive with Larrys Wild Side. Most of the islands east side has never seen a diver and the reefs show it. Many more soft corals, lots of turtles and plenty of rays. Its also rough seas (interesting boat trip) and heavy surge. Larry and his mate Eddie will seem gruff to some but the diving is markedly more challenging out east and their do exactly what I say, exactly when I say approach keeps the danger to a minimum. Back on shore (or better still, at the nearby Jibe City Bar, where Larry has his own monogrammed bar stool), theyre both a hoot to hang out with.