serrano may be a in/out camp but maybe what your looking for is more of a dry camp.
imho serrano is at the top of the list, when i got there the rangers were raking up the camp next to us. i looked for Any trash and found NONE, not a butt or a plastic bread closer, no trash anywhere. the toilets and showers were quite accessable and clean and well lite at nite. and the sm general store across the little street was well stocked. the rangers drive thru regularly with leaf blowers cleaning the pads, streets and walks and in the evenings drove thru selling their firewood. plenty of uncut

trees and small animals abound. yes id rate this as great.
now the camp ground at green valley was quite abit different, much older and abused looking, did find trash on grounds, no showers, womans toilet didnt stop flushing and no sink water. many were using mens r/r to shower at sink making floor wet and soapy. pads were in need of repairs. the campers next to us were a little trashy with their stuff blowing thru camp. this looked more standard, unfortunately.
on the other side of the lake at the barton flats camp which are second to serrano, also clean and well maintained but store is futher and not as well stocked. just my $1.43 worth.