Hello 904carrera, thanks for your question.
Your GMAT is fine, but if you could bump up your quantitative score to 80% or higher, that would be safer.
I don’t think it’s necessarily a mistake to apply R3 to the top three programs, as long as you know that it is a long shot at those programs and that you might have to turn around in a few months and tackle reapplications (and report on what is different about your candidacy from the last time you applied). Sometimes, if you haven’t had a promotion or acquired new responsibilities, it can be tough to speak to what is different about your candidacy.
One question I’d make sure to answer clearly and definitely is: Why exactly do you need an MBA? And, I would answer specifically, not broadly. Demonstrate to the admissions committees that your desired career path necessitates an MBA. Identify the specific gaps that stand between you and your short- and long-term goals (knowledge, skills, experiences, network, etc.) and show how business school would directly address those gaps.
I hope this helps!
Best of luck,
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