As a former New Hampshirite you can't go wrong in New England. Personally I think Vermont is the most scenic state. If you can give me an idea of your interests might be able to assist.
If coastal travel is your goal RI is nice around Newport, Mass Cape Cod or North of Boston Salisbury. Like Defedora said if history Boston, Quincy area is a definite must. Boston much like Pittsburgh Pa is campground challenged and your best be would be Normandy Farms or if you have access to Military installations Hanscom FAMCAMP is doable. For Maine Acadia NP is a winner.
If interested in NH or Vermont give me a shout and I will help you out.