I think a 2 day gathering might be best. It's very difficult and inefficient to shop and get around NYC with such a large group. I will only be able to attend one day, though, so someone else might want to organize the day that I don't attend (probably Sunday).
Angie, if your schedule prevents a Saturday gathering, I hope we can at least meet for tea and a waffle.
Michelle, in all seriousness, I know this is a massively expensive undertaking. We are just being pushy so you know how very much we want to have you come. But no one will resent you if you decide it isn't feasible. NYC is NOT a cheap place to be, and I know that better than anyone. That said, it would totally be worth cutting out other stuff in your budget