What I'm wondering about is if you plan on working in Biglaw, how would you work out the Friday afternoons?
Not the OP, but in a similar position in terms of biglaw. I'd be lying if I said I don't think it will be an issue. I have been known to search big firms' websites for religious sounding names and YU graduates. However, in New York, there are many, many, shomer shabbat Jews in biglaw firms. (If I'm not mistaken, the Chairman of Sullivan Cromwell is one of them). It doesn't hurt that in the summer, it's not that big a deal. Outside of New York, it's harder in a way, but easier in a way. It is less likely that a critical mass of lawyers will have to miss a day in the middle of a big deal or case, since there might be only one shomer shabbat lawyer in an entire office. On the other hand, being the only person in the entire office who is not available on Friday afternoon and Saturday might be hard to justify or explain.
I guess more generally, I will make sure to leave as late as possible in the summer, and be available as early as possible on Saturday night in the winter. I am looking at cities where the commute is much much easier than it would be in NY. If downtown is even walking distance, in a pinch, one could theoretically work until sunset, which is 4:20 at the earliest. (I will not get into a discussion of taking a subway home from work on Friday night.)
Another big question is whether to wear a yarmulka to interviews, callbacks, and the office. I welcome input on that.