Sorry it has taken so long to reply. We've both been on vacation.
While I am not sure your GMAT would keep you out, if you feel you can raise it, a higher GMAT certainly can't hurt at the schools you are applying to.
We have worked with successful applicants to both HBS and HKS and I think even the joint program, but I'm not positive about the latter. We have also worked with successful applicants to the other programs you mention.
In general I'm not keen on applying only to Harvard or only to Stanford or only to any of these elite programs because they are simply so hard to get into. However, given your age, your strong experience, and the fact these programs don't get too many applicants from Libya with your international experience, I think it can make sense for you to apply first and only to Harvard if you are so inclined. You can then apply to the other programs second round or even next year.
If we can be of additional help, please let me know.
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