A couple of options.
Virgin Gorda in the BVI's. Stay at Little Dix Bay since you're not on a budget . Dive with DiveBVI, they'll pick you up there. Most of the dives don't exceed about 60' yet there's some good coral formations, the wreck of the Rhone, and other good sites. And DiveBVI is a first class operation, they take total care of your gear once you drop it off, including daily setup and cleaning.
It's very quiet island, the goats outnumber the people. Lots of dramatic scenery but not a whole lot to do other than snorkeling at the Baths or hiking. They have several really good restaurants. Rock Cafe is one of them. There's a buffet at Leverick Bay on Fridays that everyone goes to. Tortola would be another option, all types of resorts and it's a much bigger island. Some of it is pretty isolated though, it's a really long island.
Everything in that area revolves around boats. There's fast ferries between the islands and all sorts of charters. Stop by Willy T's for lunch when you're in the area. We started our trip with a couple of days on St. Thomas, then a week on VG. With the ferry schedule, it was possible for my friends to leave VG one morning for a 1PM flight from St. Thomas. We just spent a short time on St. John, but it looked pretty peaceful. There's some local diving there also and in the Cays nearby.
Curacao might be another option. Either the Marriott in Piscadera Bay or Lodge Kura Hulanda out on the West End. Both have onsite diveops. Kura Hulanda is a little remote from everything else though. I was in one of the suites at the Lodge, they're very nice. It's one of the leading small hotels of the world. The Renaissance might have opened in town by now also. There's shopping in town, casinos etc. It's on the same reef as Bonaire so you get the same great diving (mostly small stuff) with a lot more topside. There's a dolphin dive at the Seaquarium, it's booked through Ocean Encounters. Parts of Curacao are a little seedy though.
I've been to both Roatan and Utila in the past year. While the diving was very good and there are some nicer resorts on both, the bugs were enough of a nuisance that we've decided to go elsewhere in the future. Utila is so small that except for less than a dozen restaurants in town, you'd do most of your meals at your resort. Utopia Village is a new upscale resort there. Most of the island is un-navigable by foot/car.
Roatan has a much more developed infrastructure, besides the resorts mentioned previously, there's some nicer ones in West Bay. The West End is the main touristy part but you can stay nearby and still experience it. Some good restaurants in that area also. Anthony's Key is about 10mins. from there. Cocolobo also looked good, we stayed at a house just down from it. But no beach in that area except Half Moon Bay in the West End. There are some resorts on the beach in West Bay but Deet is highly recommended, the sand fleas chewed us up pretty good.
Some of the best diving we've done was in Maui. The clarity of the water is amazing. You have access to Molokini, Lanai and sometimes Molokai diving from there. Sharks and Turtles are almost a given and Manta's are often seen. Since the substrate is volcanic and not sand, the coral formations tend to be smaller and less vivid. However there's some amazing dives in and around the lava tubes, a couple not to be missed are anything at Molokini and the Cathedrals off Lanai. Both are easy dives suitable for all skill levels.
In south Maui, either the Grand Wailea or the Four Seasons are nice. Or the Ritz-Carlton in Kapalua - a little more removed from everything in West Maui. And there's every imaginable topside activity, shopping, the Maui Ocean Center is worth a look, helicopter tours, the volcano at sunrise, parasailing, world class golf etc. Can be a little congested in some areas like Kaanapali at times.
Haven't been there yet, but Turks/Caicos is on my short list. Supposed to be great wall diving and really nice accommodations.
