Any out island of the Bahamas. Eleuthera and Long Island are THE two most laid back locations in the world. On Eleuthera, I bought a 40z of Bacardi Premium Gold for 9 dollars when I was 15 for my rents. No crime, no worries, no fat-ass tourists, or touristy type places. Don't expect 5 star resorts, expect 6 people on 9 miles of white sand beach, cool locals, world class fly fishing for bones, permit and cuda, and  2 lobster tails for 10 dollars.
Favorite place in the world.