so far the responses in this thread have been very shitty.
Revy doesn't have a park, pano doesn't really get pow, kicking horse, fernie, and whitewater have parks, but they are very small and horrible. All have excellent terrain. (maybe not so much Pano - never been there though)
Red has an ok park, can have good pow if your lucky, excellent terrain but hard to get to though.
Whistler is your best bet for a good park and pow - it's very busy and expensive though.
If you don't mind mellow terrain in exchange for a good park, Silver Star, Big White, and Sun Peaks are options, but they lack the real mountain feel.