While statistically NH may be "worse" than NYC, we're talking about a city of 130,000 that covers 20 square miles. Plus, one can avoid what people consider the "bad" areas of town by using a route hugging the shoreline of New Haven, which is a pretty nice ride in itself.

I will agree that travelling along the coast will be busy, esp. from New York City to New Haven. A more inland routing will avoid most of that, but it will definitely be hillier.