I think your approach is correct re: trying to balance out the typical weaknesses of your profile with your volunteer work and your leadership experience on the job. More generally, focus on *any* way you've made a positive difference for the people around you, both at work and outside of work. This kind of thing will help you WAY more than your GMAT (even though your GMAT's great) and your grades in college. Your familiarity with multiple cultures and languages will also be something you should highlight.
I think your odds of success at Georgetown or a similiar program are good. Berkeley and NYU aren't guarantees, but your odds of sucess are good enough that it's worth a shot. Not surprisingly (for you and for everyone else), H/S/W will be your longest shots, but I also think it's worth taking a shot. The odds of you getting into at least one (as long as you do the things mentioned above) are good enough that you wouldn't be wasting your application fees by applying.
But, just keep in mind the acceptance rate of each of those schools. They're low, of course, so spreading your bets (like you're doing) is smart.
Scott