Besides being expensive (or not) for you. This would be ideal for you. I think most people here want to mind their own business both in public commute and outside. Ton of things to do on solo there is always the Moviepass. If you don't interact with others why would anyone want to reciprocate that. Car is absolutely not needed in NYC most people love that about the city just be ready to take into account the delays and most recent downtime and service cut-offs.

This is same as any other huge metro-city. We obviously don't have mountains to hike near by, but LIRR or AMTRAK can open up few possibilities. Maybe go to Tripadvisor and Yelp and check under things to do, see if you like whats listed.