What sort of cache do people look for ? I reckon there are folk happy to do a longish walk, say 10 miles, to find one cache, others happy to do a short walk only, possibly with the kids. There are the historical sights and viewpoints and also the puzzles with or without much walking. The quality therefore depends a lot on what you are interested in. In any one area I reckon you need a variety to keep everyone interested and not just a few folk putting out their favourite "type" of cache.
Remember variety is the spice of life, allegedly.