I can try to answer 5).
Work hours probably depends on your assigned team. Probably best to get all of the details firsthand from your potential team than to guess.
Now in terms of Asian/Asian-American culture in NYC, it is generally split into three groups; a) the old-timers and descendants living in Flushing and Chinatown, b) the professional's who moved into NYC to work for the banks, c) the professional's who moved into NYC to work at Silicon Alley/Media/Publishing etc.
Group a) are the people with the most Chinese culture; every weekend, extended families go have dim-sum outings at the Flushing mall with multiple round tables of family relatives. However, Flushing is a mixture of Chinese people who came to the city during the 70's and a new wave of immigrants in the 90's and 00's. So you have a eclectic mix of Chinese people who work in restaurants, aren't as educated and also the sons and daughters of kids who were brought up in the old-timers old school Chinese household who worked their way up through the restaurant chains and became owners and sent their kids to good colleges. The old timers' culture and attitude closely resembles Hong Kong and Taiwan.
Group b) are the INTJ and class-A personalities. There's a good mixture of both ABCs (American Born Chinese) and FOBs (first generation) in this crowd. A lot of my friends in this group are very ambitious and try to climb the management ladder by either obtaining a prestigious business degree (e.g., going to Wharton) or by working very long hours or by working on guangxi. As a result, socializing is very superficial. Some of the people I kept in touch since college or hang out with on weekends, I find that I hardly really know them at all; they best represent the 'jing' of Chinese people as in Shanghai and the Mainlander attitude of always being calculating for self-preservation.
Group c) are generally the more Americanized Chinese people as they work in non-traditional fields. Although the degree varies depending on where they grew up and their upbringing. You might find some Asian Americans are willing to hang out with both Americans and Asians; some will only hang out with Asian Americans but no international Asians; some will not hang out with any Asians at all. The best way to describe this is the attitude of certain Hong Kongers toward Mainlander immigrants in Hong Kong, some will accept them, some think that they are superior because of their Euro-centric upbringing despite the fact that we all are Chinese.
But in general, everyone is very nice in NYC as it is an very international city. However, you'll have to make an effort to make new friends as it is a big city where everyone hurries from one subway station to the next. But the friends you make once you do make a real friend, you can generally count on the person.
I hope this helps and this is only my opinion, best of luck to your transition,