I don't believe there is any formula, criteria or other metric that can be used to determine a price value matrix. There are just too many variables.
Location, services, amenities and time of year all figure in.
Location has dozens of variables within that sub-category. Is it park in an highly desirable and expensive place like Key West, the southern California coast or Jackson, Wyoming? Is it located in a large urban area? Is it conveniently located off a major highway? That's just to name a few.
Same with amenities. Pools, playgrounds, fitness facilities, golf courses, activities all can have varying values. For example, pools can range from a 10x30 postage stamp to full blown waterparks. Golf courses can be a run down mini golf or full blown championship golf course. Activities can be a ten minute hay ride once a day or entire programs for different age groups that run all day.
Services run from a wide spot in the road for dry camping, to the standard full hookup park, to resorts with concrete pads and roads, clubhouses, manicured lawns and outdoor kitchens on each site.
Then you can expect to pay different prices at different times of the year. Shoulder seasons are expected to often be cheaper than prime time. Special events can cause prices to rise. Sometimes, in the deep off season, the only choice is the one open park for miles and you usually pay for that convenience.
Personally, I have felt ripped off paying $10.00 for a night and felt like I hit the lottery paying $150. It just depends.