Very good to hear from you. Now in general I'm afraid I don't have really great news for you. Your 650 is gonna hurt you a lot, and make your chances at Top 20 schools very low indeed. The low end of the top 20 schools have GMAT averages around 40 points higher than your score, and given that plus your non-traditional background, your chances at top 20 schools will be likely closer to 10%. Maybe you can tell me a little bit why you are unwilling to retake the GMAT, for this is the one thing you would pretty much HAVE TO do, if you want to apply to Top 20. If you really don't want to take the GMAT again or don't have the time, that is fine, but then you will need to compromise on your school choice. One or the other, I'm afraid.
Let me now answer the rest of your questions:
2. Which top 20 US schools you may help me the most to get in, with a target success rate of at least 90% or above? (I might take package for those schools with you)
I think you may be overevlauting yourself a bit. Even someone coming from five years of strong finance experience with a 740 GMAT and 3.7 GPA does not have a 90% chance of getting into top 10 schools, more like 50% maybe. So there are no schools where you have 90% chance of getting accepted.
3. What do you think are my major strengths and weaknesses?
Strengths - Entrepreneurship, Female applicant, and you come with a very unique background. You have to see how you can translate that background into something that will strengthen your application, but it is a good starting point.
Weaknesses - GMAT, Little quantitative experience, Moderate GPA, moderate work experience
4. I am planning for 2014 batch and I still have some time, so what areas I should focus to make a strong competitive profile.
The GMAT is by far your biggest concern, and if you want to make those schools, I would suggest reconsidering a retake.
5. What should be my road map to get into a good b-school, such as by when should I finish the school shortlisting, when to start the school packages and so on.
Depends. Everything revolves around your choice of what to do with the GMAT. Once again I STRONGLY suggest a retake as you will not be likely to reach your goals with out it.
So my advice: Retake GMAT by mid-June. Simultaneously decide on schools to apply to (conditional on your GMAT score)
Then once you get your score adjust your list of schools in accordance with your REAL score.
By the end of June one or two sets of questions may be released. Then I would aim for 4-6 applications in Round 1, and then see what happens for R2 (leaving one or two schools for R2)
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