Hi fuji, I think with your new score you'd be opening a lot more doors for yourself. Congratulations, by the way.
I'm guessing you're waiting to hear from Darden and that Darden knows of your 730 GMAT score?
In any case, you landed interviews at Wharton, Booth, and Darden. This only shows that you have what it takes and that you've looked good enough on paper for them to give you a chance. How much interview preparation have you done? Did you practice in front of a mirror? Did you really give the potential questions some thought? With 3 interviews from top schools, I can't imagine that you've done something terribly wrong in your application, otherwise you wouldn't have landed the interview. If I were you, I'd see if I can get some ding analysis from the schools that rejected you and see what the problem was. Perhaps it was the interview. Perhaps it was an unrealistic goal(s). Perhaps it was something else. From what you wrote, I can't really pinpoint down exactly what it was (though your GPA is on the lower end for top schools). If you cannot obtain rejection analysis from schools, really focus on crafting your essays to represent who you are, what your goals are, and practice heavily on mock interviews. I think you still have a shot at some of the top schools, but with some analysis from the schools themselves, you can then focus a bit more on how you've strengthened yourself in your reapp; otherwise, it's a shot in the dark from your perspective.