I did the Exuma's just this past winter. Not a charter but during a boat delivery. It sounds just like what you are looking for - very laid back and mostly undeveloped, although there won't be many 20+ mile sailing days. Most being 10 miles or so with a couple longer ones. During the 9 days I spent there I didn't see a single charter boat, they were all permanent cruisers. Now that Moorings is opening a base in Nassau that might change however. The actual sailing is a bit trickier than the BVI's due to the strong currents, high tidal range and ever changing shoals. The only place I saw mooring balls was in Waderick Wells Land and Sea Park (a must see), the rest of the places you will need to anchor or dock in a marina. The Exumas were spectacularly beautiful and extremely laid back. You won't find many beach bars but there are some. It's a very different experience from the BVI's.