Hopefully your GPA won’t keep you out because it sounds like you have a lot of great experience. Is it possible to retake a class or two to boost your GPA? If you have a good reason for your GPA (ex a long illness, etc) you should find a way to address it in your essay. If not, there’s not much else you can do at this point except hope that the rest of your application speaks for you. As for me, I graduated with distinction from Cornell, so my GPA was not an issue.