While the PD numbers are about as good as you can get, they can't work miracles. If the cell electrolyte density is really all over the map, then the cells are probably sulfating. If you bump the PD into equalize/destratify mode, you will help things. My bet would be to do one of two things.
Cheap way, look up battery desulfators and get one. They all do the same thing. They feed very short pulses of high voltage back into the battery. This can knock the insoluble sulfate back to being sulfite. It MAY save the battery. My experience is about 50/50.
Better way, replace the bank just before you will next need it again.
Matt
