With an undergrad and MS in the sciences, I would assume there was mathematics in your coursework, particularly statistics? Sometimes adcoms will concern themselves with non-traditional applicants' ability to handle the rigors of the quant analysis in b-school. You want to make sure you demonstrate aptitude for accounting, stats, calculus, etc. to innoculate these concerns. You might consider taking a correspondence course in accounting if you have never had any. This can not only demonstrate commitment to b-school in general, but will also be a real help once you matriculate, particularly if you have not ever taken such courses. Of course if you end up doing well on the quant portion of the GMAT that will also help assuage any concerns. Beyond that, I don't really see any glaring holes in your profile, although admittedly, you do not give all the details. Hopefully you have some community involvement in your past--it's always good to show leadership not only at work but outside of work as well. The core essentials you definitely seem to posess: teamwork, leadership, innovation (your thesis alone will go far to demonstrate this), and maturity (age in your case will speak for itself). Avoid HBS and Stanford, who notoriously snub older candidates and you should be good (although there are always a couple of older candidates at those schools who slip through). When you apply as an older candidate, expect more scrutiny over your career achievements and be prepared to speak to why it "took you so long" to get back to school. Definitely throw in for a few top 10 schools, though. no reason why you should "settle" with such a unique profile.
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Bryant Michaels
Admissions Consultant