Your 3 are definitely big Eastern areas. Along with Cannon, NH, I'd also nominate Wildcat, NH. There is something about NH ski areas, I guess because of less touristy development near the slopes, they seem a little wilder than VT. Having said that, on an uncrowded day the terrain around Killington Peak and Bear Mtn sections of Killington,VT seems expansive or "western" to me.
Local area: Snowshoe, WV - once I was there after a one foot+ snowfall. On a day when the sun came out and the crowds died down, all the fluffy snow hanging on the spruce trees sure made the Basin side slopes look like relatively high altitude western treelined trails. Though the vertical isn't huge, the terrain in that part of Snowshoe lies between about 4100 to 4800', some of the very highest in the East.
BTW: here's an aerial view of the upper slopes of Whiteface.
http://community.webshots.com/photo/78147708/78149451HIlnNF