I've seen many law schools just talk about their overall minority numbers, like USC listing about "37% self identified minority students" on their diversity stuff. Don't worry, I highly doubt it will hurt you either way. Your score is excellent, schools like excellent scores, you're golden.
Your undergrad experience may just be a crazy anomaly, or maybe work on soft factors - PS, LOR, ECs - this time around. I am not sure on the LSD consensus on LSAT v. SAT but from my experience and LSN, supply & demand factors seem to advantage high scoring applicants pretty consistently.
To answer his question - no, it would not be unwise to take UMich. over Columbia.
For the record, I have nothing against Morningside. I even like the General Grant Memorial, random as it is. I think I am going with Michigan, and I will probably go for a JD/MA. Thanks for the comments, especially demingh.