Dear RR,
If you haven't already, you should talk to the admissions director or another admissions staff member regarding your application. If you can gain some insight into why you were placed on the waitlist, then you would have a better idea of what you can do to strengthen your application to reach a positive decision. While a higher GMAT score might help, I think it is most likely your unemployment since 2007 that might be what is giving the admissions committee pause in making a decision on your application. I think it is a positive that you volunteered during this time at the NGO, but three years is a substantial gap on your resume--especially if you plan to look for work upon completing the program. If that is the main concern, then there might not be anything you can do but wait and hope the R3 applicants are not as competitive as you. Once again, that is my suspicion and you should talk to the school directly to determine what you can do, if anything, to strengthen your application. There are always applicants waitlisted in the first two rounds who are ultimately admitted, but that number does vary from year to year and is not one schools will publish.
Best of luck,
Lisa
