Here are some interesting out of the way places.
Norman Rockwell Museum in Stockbridge MA,
Hildene, the Lincoln Family mansion in Vt. (Abe’s son)
Deerfield VT, historic villiage site of French-Indian War Massacre.
USS Constitution on walking tour around ‘Bastun’ (I realize this is in Boston, but there are some other interesting places to see there in the area, too. Paul Revere’s home, tombs of John Adams and john Quincy Adams, and several presidential libraries)
Sturbridge Village and Mystic Seaport are fun if you have kids who are interested in (or should be interested in) history. There’s also the Shelburne Museum in Vermont. You can also see the houses of sculptors Daniel Chester French and Augustus St. Gaudens if that’s your thing. Art museums in Williamstown and contemporary art center in North Adams. The Lenox/Stockbridge/Lee area in the Berkshires is supposed to be nice as well. Edith Wharton’s estate in Lenox may or may not be open (money problems).