We're in Bar Harbor ME now...got here yesterday. We went to Mystic and loved it. The Mystic Seaport museum is great. Your ticket is good for 2 days, so we split it up. Eat at Mystic Pizza in town. It was really good, plus we had a nice view of the main street. We stayed at Seaport RV and Campground. Liked it a lot, and it's close to the town. No sewer, but if you stay 3 days or longer, there's a free honey wagon. Super long pull-thru sites (they also have back-ins).
Newport, RI was wonderful. That was a surprise to me - I loved it. I would definitely go there. See some of the mansions (or all..we opted to not see all of them) - drive Ocean Drive. It rained, so we missed Cliff Walk. I wish we had stayed longer there. We stayed at Wawaloam in W. Kingston RI, which was okay, but there are others. There's a state park in Narangasett (sp?) - Fisher something?? - they were booked and couldn't get a site. We took a ferry ride to Block Island. It leaves from Narangasett.
We stayed at Bayview CG in Bourne, MA (nice place) and took a ferry ride from Woods Hole to Martha's Vineyard. Very touristy, but glad we went.
Old Orchard Beach, ME is extremely touristy and carny-like, but I like to see all the different places, so an hr. walk-thru was fine. Coming from FL and seeing their beach was interesting. Portland, ME was nice for a 2 or 3 hr. walk around and lunch. We stayed in Scarborough, ME at Bayley's CG, which was close to both of the above.
We've been to Boston, so decided to not stop there this trip. If you haven't been, then I would definitely add it.
Enjoy the planning and your trip. It's beautiful.