There have been a lot of different topics of discussion going around, but just wanted to comment re: being a frum associate and therefore being unavailable on Shabbos. I'm sure there are firms where they really don't like it and it'll hurt your chances at partnership, but that's far from the case at every firm in NYC. My firm is super understanding and accepting to the extent that if I'm cutting it a bit too close on a Friday, they'll basically throw me out of the office because they don't want me to be late. As long as you're willing to make it up, they don't mind it at all. This year, two frum people got promoted to partner and least year there was one.
It's a give and take. There have been times when I needed people to cover for me on Shabbos because it was smack in the middle of the busiest time of the deal, but I've also covered for people when they had family situations and they needed to be offline. If you're committed and work hard, and that means working late on Saturday nights to make up for being offline on Shabbos, at least IME, being frum won't hurt you in terms of getting staffed on deals.