Hey Daniel,
Those are all solid questions--you're definitely giving your law school candidacy some serious thought (I wish more people did that--it's important when considering any sort of post-graduate degree, and certainly a necessity when it comes to a JD). Here's my take on your situation:
1.
Where do you stand pending a 165+ LSAT? That's hard to say without knowing which schools you're considering. I've said it before, and I'll say it again--law school is a numbers game. You can't really have a solid idea of anyone's chances until you know what they're aiming for. If you told me you were aiming for Harvard and Yale (where both of your main numerical indicators fall well below what they even consider), I'd tell you your chances were extremely, extremely slim. If you told me you were aiming for George Washington (where you would be at or around the median in your numbers), I'd say you had a high probability of acceptance. It's all relative to your school choices. With a 3.37 (considering that you'll get bonus points for your last three semesters, and a slight boost for your 3.8 grad GPA), and a 165+, you stand a good chance of getting into the bottom half of the T30, and a very good chance of getting into multiple T50 schools. I would put the T14 out of reach, for the most part, unless you were able to break into the mid- to high 170s with your LSAT (and, even then, it's never a sure thing--not with schools at that level).
2.
To what extent is your grad school GPA taken into account? I've already covered that pretty extensively here:
http://blog.powerscore.com/lsat/how-do-law-schools-look-at-graduate-work/ - Take a look at that post and tell me if you have any questions. I'm glad to answer them!
3.
To what extent are your extracurriculars considered a plus? Again, hard to say. For some schools, specially those in the higher echelons, it will certainly add an extra, positive dimension to your application, and may give you a slight boost. At the very least, it demonstrates that you are committed to academia, and are considered an expert/scholar in your field--that alone will help, since it will show schools that you likely have the academic chops to succeed in law school. However, this also depends on how you're focusing your application and what your plans post-JD are. If you're considering going into teaching, then it will certainly help bolster your application; if you're considering going into litigation, it probably won't make much of a difference.
A few things you have going in your favor:
1. Your highest UGPA grades came at the end of your college career. That's going to be very beneficial for your otherwise-slightly-low GPA. It shows that you got your act together and really shone when it was most difficult.
2. Your LSAT is likely to be pretty elevated, simply given where you are right now after just two weeks in. A high LSAT score will go a incredibly long way to smoothing the path to your acceptance at a top school. As I've said before, the LSAT is considered an indicator of first-year law school success; therefore, the higher the better. Also, given that you've been out of undergrad for three years (four at the time of your application), your LSAT will be taken as slightly more indicative of your academic potential.
3. You have definitely shown an interest in academics. Law schools like that.
I hope that helped! Please let me know if you have any further questions.