Thank you for all the information. I think you've been very thoughtful in your school choices -- I commend you on being both realistic and taking into account your own goals and needs when considering target programs!
As you know, you fall into that fiercely competitive demographic of "Indian Male Engineers," so you'll want to try to position yourself more so as a consultant and play up your business contributions to your previous company/clients moreso than your technical achievements. Taking into consideration your extracurricular, community, academic and professional profiles, I would say you're an average candidate within this demographic.
The real challenge is that you are applying as an unemployed candidate. That is going to be tough. The other thing is that it seems you haven't used this time to do anything else really (e.g., fulfill a lifelong personal ambition, get involved extensively in a nonprofit that you are passionate about, etc.). I definitely suggest that you find a way to weave your decision into your career narrative, and yes, I think it warrants an optional essay.
Taking this into consideration, I feel that Duke may be a bit of a reach school. I might suggest that to compensate, you add another somewhat safer school to your list (e.g., Rice, Texas A&M, Wake Forest, Tulane in the regions you specified).
Hope this helps,
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