in Colorado the powder is tracked out within an hour or two, so why not ski park.
in Jackson you have more like half the day to ski good powder and even longer if you're really going off the beaten path for it, but a lot of times they don't even open their park
the perfect park powder day is with about 2" of fresh. any more and it will slow you down and get tracked out/sloppy, but just a little bit of soft snow goes a long way on the landings. <3