I think the answer is "it depends". If you don't want to travel half way around the world, the best options lie in the Caribbean. From there, I think there are two big questions: (1) what kind of atmosphere do you want topside (2) what kind of diving do and diving activities do you like (walls, shore diving, drift, doing photography, etc.
I do underwater photography and have explored most of the Carribean. On my short list for best diving, quiet topside, safe and relatively disease free are Bonaire, Grand Turk, Saba, ST. Lucia and Cozumel. I notice a lot of people like Cozumel and I have a couple of comments about that. Travel to Cozumel is cheap so the high volume of divers to that location increases the likelihood of people responding liking Cozumel. If you don't travel a lot, you're likely to enjoy any place you go if the water is warm and the reefs are healthy. Cozumel just barely makes my short list for two reasons: (1) you can't drink the water and you're much more likely to have intestinal issues (2) it's drift diving that doesn't work well for most still photography. If you have any questions anytime about hotels, dive operations, feel free to email me. If I've been there lately, I'll offer my opinion...tom