Thanks for your post. So you are aiming for R2 deadlines, coming up quickly, if I'm understanding all correctly, so you'll def have the 640 GMAT. On the lower side for the schools you mentioned but wouldn't rule you out entirely with a great application. Marshall might be the bigger stretch of those on the list. Generally military experience can be a plus-- and certainly being a marine says a lot about your character and dedication and work ethic usually (at least that is the preconception). You would likely have some strong leadership and teamwork experiences to draw from in your essays, and subsequently in the classroom, and likely international experiences as well. The challenges coming from the military are a) ensuring you can talk about what you've gained from your experiences that will be relevant in b-school (and your career), and b) ensuring you have a clear explanation of your goals and WHY you want an MBA. As long as you manage those 2 facets well, you would likely be in good shape.
Yes you can briefly touch on the score in the optional essay if you feel it's not entirely reflective of your ability to excel in b-school. And in terms of other experiences and awards, it sounds like they will all add dimension to your profile so I'd include where you can.
Let us know what other q's you have, and keep us posted! Good luck!
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