I was in New York in April for the first time also.
Avoid Empire State Building (ESB) the view at the top is a joke compared to the Rockefeller Center "top of the rock" (TOTR).
With ESB we experienced about a 3 hour queue only to experience a grid like view when we finally got to the very crowded observation deck.
TOTR you buy the ticket then come back at your alloted time and you are straight up to the top taking in the magnificent view.
Also the view is better from TOTR because:
-You're higher up, about 20 storeys higher than the ESB
-You get the view of the ESB which is an iconic part of the Manhattan skyline.
I told myself and my wife that we must make sure to tell everyone we know going to New York to not waste their time with the ESB.
You are the first one to be warned. We wished someone had warned us !!
Also for Statue of Liberty if you want to go up to the crown or to the pedestal, you need to book several months in advanced. You can book online just google.
DO THIS NOW.
Enjoy New York. A week for us was not enough. It was the highlight of our trip and that's saying alot considering we took in Hong Kong, Istanbul, San Francisco, Miami, Los Angeles, and Fiji.