The advantages of NYC Midtown is anyone can get to it from anywhere in the
city; there are lots of options for start-ups. Almost every subway line
goes to midtown in some form or another.
The advantages of Brooklyn is usually price, but unless it's on 1-2 stops
out of NYC; it can be difficult to get too unless you already live in
Soho house is very nice, but too crowded for daily work and more of a
social gathering and meeting place. There are a few WeWorks around the city
that work well. Again, NYC places are usually crowded.
I highly recommend Workhouse on 46th. When I worked from there, I loved the
options, the view, the rooftop and I always had a nice place to meet
customers. The decor is nice and it feels professional.