You have several strong options in the Big10, including UIUC, MSU, UofM, Purdue, Penn State and UW Madison. What do you consider rural? UIUC is in Urbana/Champaign, but once you are outside of town it is cornfields to the horizon.
Northwestern is a hair small, but is an outstanding school that is strong in just about every field. It is also near a city rich in culture and entertainment.