The OGA hiring managers do not care what your BA or BS is in. Heck, I left AD in 2001 to take a USG job and didn't actually graduate with my degree until 2003. I've worked with people who had JD, MBA, and one of the sharpest analysts I ever worked with had a BA in Philosophy. They all could WRITE VERY WELL, were very organized, and conducted amazing research. Regarding languages, it is very common for OGAs to hire someone only to retrain them into a needed language. I know guys to were 2/2 in French, Spanish, and even Russian and all 3 were retrained into GWOT languages immediately after hiring.
Here is a dose of reality: all that cool shit you think you'll be doing working as an OGA civilian...it's only in the movies man. If you want to do really cool stuff that you cannot do because of military restrictions, become a contractor that supports OGAs. High risk, high pay, and very rewarding. Just remember...they are expendable: not as in their life is expendable but as it "thanks, the project is over and this contract is terminated. Have a nice day."
Quite accurate really. We had some OGA recruiters come out to Texas Tech earlier this year, and one of em put it best when he said "whatever degree you can think of that is offered here, there are at least several people back at the agency that have it".
To your second point, from what I've heard that's yes and no. Buddy of mine who was Marine infantry for four years before getting out worked for blackwater for the longest time (or whatever they call themselves now) until recently and did a few interesting protection gig's and such, but when wanting to move into something like kidnap victim recovery and other really high speed shit, he basically got told "unless you have a SOF background your not gonna be able to do those kinds of contracts". Sadly he's leaving the company due to the corporate mindset they board there is running things under now.