You might want to look into Frederick Law Olmstead and Calvert Vaux if you are investigating physical planners of New York City. They designed and supervised the building of Central Park and Prospect Park in Brooklyn and thus had a huge impact on the shape of the city. One of the facts that I find absolutely fascinating when I teach my course on Novels of New York is that the grid of the city all the way up to and through the park was laid out decades before “uptown” was actually developed. You can see pictures of Manhattan with the streets laid out and farms in between.
Another big factor in the development of the city was the construction of the Erie Canal which allowed goods from upstate and inland to be brought to New York’s harbor for exportation. This took place in the early part of the 19th century.
Unlike smaller cities which may have had only a few builders or project managers, New York has a long history of evolution and growth which is why I suggested the excellent documentary cited in my first post.