Joseph Leonard is one of my favorite cozy spots for brunch on the weekend. After a long week of work their avocado toast and a bloody mary hits the spot. Get there early or expect to wait, it's small and limited seating. Their sister restaurant Jeffreys Grocery across the street is also very good, but no expresso drinks which and I need my morning latte.
Within an couple hours' drive of NYC, you can find lots of sleepy seaside towns. Not only can you get your soft ice cream and salt water taffy on, but you can still spot cool, hand-lettered signs and other relics of a past generation's amusements.
My second-favorite outdoor-place in Manhattan. The abandoned 1.6 km rail tracks running above Chelsea down to the Meatpacking district were turned into an above-ground park. Perfectly nice place for sitting in the sun, reading, relaxing, having lunch in some green spot in the city. Nice views at the Hudson River, New Jersey, the Statue of Liberty (little small from there but still visible) and the architecture around Chelsea.