Tough question, you substitute the NY crowds in VT with the Boston crowds in NH. Cannon has the best terrain of the three you mentioned, but it can be icey. If you are in North Conway, you have access to Attitash, Wildcat and even Bretton Woods.
Anyone been to the above resorts before? Might be hitting up NH one weekend (wanted to see how NH riding is compared to VT). How are the trails, weekend crowds, etc?
Loon and Cannon are great fun. Stay in Lincoln. The Comfort Inn has a heated indoor pool and hot tub, and you can see the slopes at Loon from your room (we just got home from four days there). Loon has lots of options, lots of terrain, and a much bigger mountain feel than Southern Vermont mountains. It is just a couple hundred yards to the interstate, ten minutes up to Cannon. Cannon is awesome...and steep. The blues at Cannon are like the blacks at Mt. Snow or Okemo or Killy. And the blacks are crazy fun!
Don't listen to the other guy the vibe is much better than Vermont. Vermont attracts all the New Yorkers coming up 91. Nasty, rude, loud. Loon and Cannon are very laid back by comparison. Boston people are just more mellow. Friendly. Happy. Having a good time. New Yorkers always seem to be in a rush, while the Boston crowds at Loon and Cannon were pleasant and just having a good time. We loved it. I wish it wasn't such a PITA to get there from eastern Connecticut farm country!