Anchorages I find tend to be quiet and often have had to myself:
Maybe Big Carter's
Paw Paw (in settled weather
Bay at north end of Manjack, though it now has a cottage in it.
Pelican Cays (day stop, maybe overnight in settled weather)
Bight of Old Robinson
I second what Vasco said about north being quieter.
Photos of most of the above and a few anchorage maps on my webpage: www.bahamasmariner.com
(still in progress, pardon the mess)