If you want less touristy we went to Exuma in the Bahamas last summer. Nice island and if you rent a car easy to get around in. Cool beaches and we were the only ones at many of them. Good snorkeling as well. Not a lot of reefs though so you won't see as many fish as you would in GC which I have been to as well and as mentioned is very nice, especially 7 mile beach area. Not a lot of high end restaurants but good local ones. We stayed at Grand Isle which if you saw the Frye Festival Documentary is right next door to where that disaster was.