Wow, that's a pretty interesting background! I see what they're saying about boosting your quant score, but I still don't think that you need to.
First, you have a good GPA with some rigorous courses. I don't think that a b-school will look at you and worry that you don't have the necessary intellectual horsepower. Second, you have done enough interesting things that adcomms will focus on those more than something as mundane as your quant GMAT score.
Put another way, I really don't think that your quant GMAT score will keep you out of business school. You may decide to do it, anyway, but I'd advise focusing on the other parts of your app. Remember that adcomms look at your total app, not just any one part. When they look at the whole, they'll know that you're smart enough to hack it in b-school!
Scott
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Co-Author, Your MBA Game Plan