I'm just outside of Hartford... NYC is a pretty impersonal place to meet, and for the price of getting there/parking/doing anything we could probably have a much better time somewhere more rural.
It depends on how centralized you'd like to make things. Pretty much anything (that can reasonably call itself "north east," with the exception of maybe parts of Maine) is going to be 2-4 hours max for folks like Delirium and me, but could push 8 for others depending on where you'd have it.
The Connecticut/Mass border has a nice location of its own at the New England Air Museum. It's extremely close to the hotels near Bradley International, and is also well within range of outdoors pursuits. There's probably a camp ground or two somewhere up that way, though I'm not sure.