I didn't see you mention when you were planning your trip.
This information is very valuable. It gives those who want to help you a better understanding of what to suggest as well as guidelines as to what might be closed.
Gettysburg would be my first choice for Civil War attractions. For mansions try Newport, RI. For general historic there's so much in MA-Old North Bridge, Minuteman National Park, Lexington Green and the towns of Lexington & Concord just to name a few. Nashoba Valley Winery in Bolton, MA is very nice. For something different do the tour and tasting at Moonlight Meadery in Londonderry, NH. There's a craft beer house right next door. For lobster there's just too many places to mention!