Best clear blue beaches in the caribeean for honeymooners?

Question

Well we will be getting married at the end of July and we def. know we want to go somewhere tropical with beautiful beaches, good food, fun activites, yet romantic and with not a bunch of kids running around all over the place. We both have been to Cancun several times and we are afraid we will not find another place to top there clear blue beaches that are gorgeous!!! So any ideas of where to go????