You have tons of time before your applications are due, so there's no real harm in retaking, unless you're convinced that you've already maxed out your GMAT score. But I would argue that the rest of your profile (GPA, extracurriculars, undergrad institution, quality of your recommendations/projects/promotions, execution on your essays, etc.) are going to matter a whole lot more than an extra 30 points on your GMAT.
A balanced 690 is fine, and there are plenty of white male consultants with 690s running around the schools you mentioned. There are also tons of white male consultants with 750s who get rejected from those schools every single year. Would a higher GMAT score help? Sure. But you're in a pretty competitive applicant group, and it's much more likely that you'll get into the schools you mentioned if you manage to stand out in other ways. Evidence of interpersonal or extracurricular awesomeness will give you a bigger advantage than a few dozen extra points on the GMAT.
But if you think you have room to improve on the GMAT, why not go for it? You'll still have plenty of time to thoroughly research programs and write some killer applications over the summer.
Good luck with everything!
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