1) CFA Level 1 will not make up for your "average" GPA
2) You said it yourself, you are not interested in finance and that will probably show on your essays. Having CFA Lvl 1 on your resume will only confuse the adcom (since your work background is completely unrelated as well) and your application will be all over the place (without any direction)
For example, let's say that you are applying to school X and this school X incorporates current 2nd yr students or alumni during the interview process. As a current 2nd yr or as an alumni, I will be very confused if 1) your essay reflects that you want to do something else other than finance after bschool, 2) you have CFA Lvl 1 mentioned on your resume, 3) your work experience is in software.....
3) UG GPA is less meaningful as your work experience (in terms of yrs) increases
4) you don't need to have exposure in finance to get into a top business school
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