You have been encouraged to broaden your notion of school quality and move away from the overall ratings from US News. If you had a choice between a top 20 and a top 200 school, that would be a meaningful difference but since there are over 2,500 four year institutions in the US I would agree that the difference between 120 and 140 as ratings for the university as a whole are not very meaningful for someone who is going to declare a major in a particular department. Within any university, some departments are better than others. NIU is not for you since you are interested in an urban school, but the idea that NIU is SIGNIFICANTLY worse than UIC is silly. Worse for what? I am guessing more students go there to major in education while more students go to UIC to study health fields, but I can’t imagine anyone suggesting that the undergrad program at one is significantly worse than the other. A few links suggest that NIU is a good place to go for business and another recent link showed that it is considered a top underrated school in the US.
http://www.accounting-degree.org/best-accounting-schools/
http://www.accounting-degree.org/best-graduate-schools-for-accounting/
I’m just posting these as evidence that the overall US News ratings don’t provide much useful information on how various departments are viewed, not because I am promoting any particular Illinois school. I’m actually more familiar with UIC than NIU.
I suggest making a list of schools in Chicago, New York, and LA and sending out some applications to see what happens.