The further up north you go, the better it gets.

I basically grew up at Camelback (we had a condo that was right next to the Terrain Park)... that place is over crowded now and over rated. Although im not big on snow tubing (closest i get to tubing is passing by the tubing area on my way to go skiing), it does look like Camelback has some good runs.

Check out Jack Frost/ Big Boulder.

A little further North you can hit up Hunter Mtn, NY.

For the best experience, I'd go to VT... Mt.Snow is family friendly and there's lots of great places to eat and go out afterwards. Though, on that note, depending on what you're looking for you should check out the snow tubing times.... if you want to do "night tubing" you need to make sure the mtn is open later.