I highly recommend St. Kitts.

It is a beautiful unspoilt island with lots of friendly and helpful locals.

You can easily rent a jeep and explore the island or visit the sister island of Nevis.

You can stay in a lovely plantation, a B&B, or a quiant inn.

There are also a variety of snorkel and dive sites on the island.

Check out http://www.myislands.myeyez.net

Turks and Caicos

Bonaire speaks to everything you want..or The Grenadines.

Though it is not on your list you might wish to check out Hollywood Beach Resort in NOrth Caicos. It actually sounds just like what you described. And they, unlike Grand Turk, did not have hurricane damage.

Have been to St. Kitts, St. Martin, St. Barts, and sailed throughout the Grenadines. IMHO none have GREAT snorkeling. The best we've seen in the Caribbean was shore snorkeling from West Bay Beach on Roatan. Amazing! Roatan can't be beat for diving either. While Roatan does get a bit of cruise traffic, we didn't find it disruptive in the least. We rented St. Mac's Villa in West Bay Village. Wonderful three bedroom with a huge porch, right on the beach. Dive shop practically next door and we did shore snorkeling every day.

http://www.westbayvillage.com/

http://www.roatanet.com/islandpearl_f.htm

I have been going to St. Kitts since I was a child (my father is a Kittitian) and I am moving down next month.

Diving isn't as popular in St. Kitts as other Caribbean islands (such as Grand Cayman, Cozumel, Belize) but there are some nice dive and snorkeling spots.

You might enjoy Timothy Beach Resort. www.timothybeachresort.com

St. Kitts is a very laid back, unspoilt and safe island. Lots of friendly locals who will make you feel at home. Fun beach bars you can enjoy a cold drink and delicious seafood. Beaches aren't crowded, and lots of island excursions you can enjoy. (Rainforest and volcano tours, catamaran/snorkel excursion, scenic railway, kayaking, sea trek, golfing, casino)

St. Kitts is also a very historical island with breathtaking views. (Brimstone Hill Fortress)

You can also visit the sister island of Nevis for a day trip.

For more information on this beautiful island visit www.myislands.myeyez.net