Hello nick17india, thanks for your question.
One thing that is a potential concern in terms of top 20 programs is your GPA. What is the US equivalent? As you probably already know, you come from an overrepresented demographic in the MBA applicant pool, so competition will be fierce for you. You will be competing with peers with impeccable education profiles (GPA/school). Moreover, a 700+ GMAT score would not move the needle as much as it would otherwise, given your peer pool. Finally, practice tests can be deceiving in both directions, from my experience. I've met countless applicants who've been surprised by their actual scores (sometimes for the better, sometimes for the worse).
Ultimately, the most crucial factor for you will be the quality of your leadership experience in and out of work. Can you draw upon "moments" when you truly led: influenced individuals and organizations, drove results, took initiative? If you can demonstrate your leadership abilities through your stories, then it really doesn't matter if you don't come from more traditional industries like finance or consulting.
Best of luck!
Brian