The lesser known but very nice alternative is SIBL: Which has nice workspace in its lower level reading room. This is more quiet like a university, and not like a hip/trendy etc. But they also have photocopy, print, and research materials if you should need some.
NYPL: Science, Industry and Business Library (SIBL)
NYPL: Science, Industry and Business Library (SIBL)
188 Madison Avenue @ 34th Street
(917) 275-6975