Bonaire - been there 9 times, the first few times were great 20 years ago. My last time there 5 years ago was just that, my last time. The pollution, over development, degradation of the reef plus the expense of getting there takes it off my list.
Cozumel - not a favorite.
Saba - I honestly don't know why people go there to dive. I was there on a live-aboard and Saba is on the top of my least favorite places that I have been.
Dominica - loved the diving on Dominica. Although fairly limited in dive sites, the reef systems were some of the healthiest that I have seen in the Carib. It is on the expensive side both to stay and to get to but the diving is pretty good.
Nevis - not even a dive location in my opinion, just some place to get wet
St Kitts - ranks with Nevis
Roatan - Similar to Bonaire, 20 years ago nice diving. Not great but nice. last trip was 4 years ago. would not go back.
Utila - I like the diving in Utila. I have been there many times. Probably 200+ dives. I know the dive sites as well as or better then most of the dive masters, that being said I can tell the boat captain which dives I do not want to do. There are some dive sites there that are not worth doing and there are some that are very very good.
Bimini - what? why? got wet..
Cay Sal Banks on a live aboard. Decent but was surprised at the poor conditions of the reefs considering how remote this place is.
Channel Islands CA. could be great I suppose but I hate cold water diving so not a fair assessment.
Cayman brac - would not go back
Little Cayman - way over rated in my opinion. Have done better diving on Utila
PNG - very good diving. very difficult to get too. Very expensive for what you get. The Philippines is much better in my opinion.
Ticao Island, Philippines - awesome!!! . Incredible corals both hard and soft. Amazing macro, some big stuff. Mantas if your lucky. Will go back some day.
Malapascua Island, Philippines - way over rated. The only thing that makes Malapascua worth doing is the Thresher sharks and in reality the effort and the expense to get there do not make it worth while.
Anilao, Philippines - Love diving here. Great macro, lots of critters. Some really good coral dives.
Kauai - great sharky dives, lots of turtles. Not much else. Would dive there again if I was going to Kauai for a vacation but would not go there just to dive.
Lembeh Straights, Indonesia - love it. going back soon.
I pretty much only do the Caribbean now when I have a short trip and am wanting to get together with friends. From where I live it is more cost effective to go to Asia and the diving is exponentially better.