I think it depends. I do not know how Oklahoma is, but for instance, here in Wisconsin, if you graduate from a Wisconsin law school, you are automatically admitted into the bar so it pays to go to a Wisconsin school if possible. Because I go to school in Illinois, even though I may practice in Wisc. and currently live here, I still will have to take the Wisc. bar.
You know where you want to practice....as you said, you dont want to practice in NY or LA. You dont need to go to Harvard or Duke. The best attorneys in OKL. didnt go to those schools either...they went to OU or OSU. Obviously, going to school where you are going to end up practice may open more networking opportunities. It may also get you accustomed to what OKL. courts are like, etc.