Your two proposed routes, combined, would (in general) make a great loop RoadTrip out of New York. However, Your starting point makes no sense - it's not JFK or any airport! And it's way too far from any airport to represent just getting to an off-airport site to rent the car. I will also offer two minor tweaks. If you fly into JFK airport, you can save yourself the first harrowing drive through New York City by starting out going east on Long Island to Orient Point and taking the ferry across Long Island Sound to New London CT. The second tweak would be to include Acadia National Park and Bar Harbor ME. That's a little farther "down east" (up the coast) from Portsmouth NH but well worth the extra miles. Even with those additional miles, you'd be looking at fewer than 1300 miles total (plus side trips), eminently doable in ten, or even eight, days.