I have only been to Sutton. Went earlier this year when we had a big thaw and had a blast riding in the trees even if it was spring conditions.
But in your situation, from my research, I would suggest Orford.
Bromont is probably going to be packed as it is closest to Montreal.
Sutton would be good if you were experienced as they have awesome glades but the runs seem short if you are not criss crossing across the hill and some sections in the trees if you are not experienced would be pretty tough.
Orford from what I hear is known for smooth groomers so as a beginner I would think that long smooth runs are what you are looking for to enjoy the good pow pow. Bonus, they have a gondola and have the most vert (almost 2000feet)
After writting this I am wondering why I have not been there yet...
Let me know what you decide and how it goes