Bahamas
5-star, 5-star, 5-star... 2-star? Well, The palm tree-lined beaches are pretty, but it's really kind of a hot, dry, bland area; if you're not going there to dive, I think you're just not going to see or do much. I suppose you could read and lounge, maybe write some journals or detective stories. Great diving though!
I hesitate to even call it “Caribbean” diving however, since the Bahamas are in the Atlantic Ocean and not the Caribbean Sea, but the crystal waters and shallow reefs make it similar enough I suppose (and no one like a literalist). As diving and tourism are so well-established there, it’s also relatively cheap, even coming all the way from the west coast of the US.
The spring and summer offer warm, beautifully clear waters, plenty of reefs, fish, dolphins, turtles, sharks big & small; be warned however, it’s pretty much a desert climate, and the sun can get downright brutal. Wear light but concealing layers, lots of sunscreen, and bring a big hat! I spent several days on the deck of a small private boat (looking for oceanic whitetip sharks, which can be abundant around Cat Island), and most of us barely escaped sunburn, even with full coverage. Mid- to late winter is a great time for big sharks, and it is cooler topside – but that comes at the price of much rougher and cooler waters*, and potentially iffy visibility. (*For Tiger Beach in Jan/Feb, I wear a 7mil suit, as even 75F water can get chilly after several hours at a time.) There’s no bad time to go though, and I think the region offers something for everyone – snorkeling, reefs, sharks, wrecks, deep walls, etc. I think it would be possible to spend years here, just exploring and discovering all the reefs and critters.
Getting in & out does require a passport, as close as it is to the US, but I’ve used US currency at stores. Not sure if that’s normal or not. As southern Florida is the most obvious gateway to the Bahamas, I also heartily recommend adding a few days to a trip so as to do some Florida diving. It’s a neat mix of tropical and temperate, and you can find goliath groupers, giant southern stingrays, even the odd hammerhead shark, as well as some really cool wrecks.