My wife and I stayed at Divi in September and could not have been happier and can't imagine a better experience.
There IS a very nice sandy beach there. When we weren't in the water, we were on the water. And, they have a huge float out a ways from the shore for sunning, diving (not SCUBA), etc.
We had the ocean "deluxe" room -- part of our $777 package. It was more than adequate -- two double beds, a.c., nice balcony, from which you could look straight down into the water and watch the fish.
Chibi-Chibi restaurant was handy and had good food -- about the same prices as elsewhere in town. Their buffet breakfast in the morning has anything you could want.
There is a casino, but we didn't go there, so can't say what it's like. Also a small gift shop. And a beachside palapa for beer, towels, swimming floats, etc.
The dive operation was first class, as were the boats. We did six days of boat dives, and only went to one place twice. They schedule the next day's boats a day ahead of time, and if there's a location that everybody wants to go to, and if the conditions are right, they'll go there.
The skippers and guides were very helpful and informative and super-friendly. And they always found the right stuff -- seahorses, frogfish, turtles, etc.
They do not limit your bottom time, other that to suggest a max depth and time for each dive, but then qualify it by saying if you're diving with a computer or nitrox, just to dive safely.
I think the best, though, was the staff -- from the maids to the waiters to the reception staff to the gardeners -- everybody. Everybody must have taken a customer service class, or else are just friendly and helpful by their Bonaire nature! And, as I said, the dive staff were #1 (although, in honesty, we haven't stayed anywhere else on Bonaire, so can't say others on the island aren't just the same).
Hope this helps. PM me if you want more info.