Hey there,
I don't think you're being too lofty but I do think you're not diversified at all. You have some great work experience - blue chip AND small business which gives you both brand and scope. That's pretty rare! From an academics standpoint you're solid - good school, good GPA. And it seems your 501.3c is kicking butt and taking names. Love that! I know you mentioned what your story would be but I'm less concerned with that because that's something you figure out per school, not overall.
But your GMAT is below the median. Now, that said, it's just one part of the puzzle. But it IS a big part. That's why I said I don't think you're diversified. You were in banking, you're all about diversification (or at least I hope you are
). It comes down to if you're focused on getting into a top school or if you're looking to get into at least 1 school. If it's the former, then go aggressive and be comfortable you might (but it's not totally likely) get dinged all around. If it's the latter, look at some schools in the 8 - 15 or so range because your chances there are a fair bit better.
I hope that helps! Let me know if you have any questions!
Bhavik