I highly recommend going to Le Massif de Charlevoix... it's the best hill out east by far. Better than Jay Peak, Mont Ste Anne, etc. Tremblant is great for partying n girls but shitty for riding. Jay Peak has good glades and gets lots of snow, but also lots of rain (base doesn't accum n runs turn icy) and lots of visitors. There's also Stowe if u haven't; it's decent. If you are only concerned about finding powder Le Valinouet in Saguenay is the place.
I'm planning a trip to Mt Massif, and will be there for approximately 4 days. What are the other nearby mountains that are within an hours drive or so of Mt Massif? I want to have the option of exploring other ski resorts while I'm in Quebec.