I'd like to elaborate on my last post. Beaches, Turks and Caicos would likely be my first choice. I just returned from there last month. They have everything and anything to make you comfortable and spoiled. The food is amazing and the activities are tops and well done. Very pampering vacation and the kids had a ball!
As has been mentioned you would be hard pressed to find another Caribbean area that could offer similar beaches and water, they are magnificent. The new Italian Village section is outstanding. I do also like The French Village very much too - just depends on the room type that fits you best. (there are so many)
I have also been to Grand Cayman many times and can easily see this fulfilling your wants in a location. Beaches are beautiful, nightlife is not so much if you are looking for that. Some of the nest meals we have ever had were in Grand Cayman. Plenty to offer the kids especially if they are into water sports, scuba, snorkel and such.
Aruba is great, Nightlife, great food, Casino beautiful low-rise and high-rise accommodations and some all inclusive also. Have a peek on Trip Advisor to see what appeals most to you and go from there.
Punta Cana and The Dominican Republic keeps popping up and I agree there are some very lovely properties, especially La Romano Casa De Campo. We were there in May for my husbands 50th we also stayed at La Romana Dreams, all very nice.
I guess making a list of wants for your trip would help in narrowing your options down. So much fun to plan a trip!

Have Fun. Let us know what you have decided.