The best way to enjoy Manhattan is from Brooklyn. Transmitter Park offers views without the crowds, and you can pick up coffee-to-go and treats from nearby Ovenly. The India St/Greenpoint Ferry is a 5 minute walk and will take you all the way to the Rockaways in the Summertime.

A stunning place to watch the ocean.

Part of the Marlow restaurant group, Diner is one of the more casual / rustic options. The menu changes daily and is written out (most likely upside down by the wait staff) on your table or the back of a receipt. The only constant item is the burger, which to be honest, is one of the best in the neighborhood. If they have a breakfast sandwich for brunch, get that. The fried chicken sandwich (with dark meat) is also a favorite. They make scrambled egg dishes better than most. Dinner is solid all around (they crush a steak for two). Homemade ketchup and dijon mustard are on every table, so regardless of what you get, these two condiments are worth the visit. 

Of all the many museums in New York, this one is the most striking to me because of the unique experience you have while viewing the art. This Frank Lloyd Wright building integrates art with architecture in a way that makes it unique to this city. No matter where you are standing you get an incredible, extremely thought out detail of his work and the exhibited work.

When I first visited NY in 2010 the New Museum left a permanent impression. I love the architecture and the concept of the piled-white-shoe-box look-a-like building at the edge of the Lower East Side neighborhood. The exhibition program is appealingly different, and the bookstore in the foyer is not to be missed!