mojo-
2 years ago I was basically in your exact same spot.
I had worked as an IT consultant for 3 years, didn't hate it persay, got to work on some interesting projects and definitely make a lot more $$ that I had before. But I also was really getting into traveling / foreign affairs / social enterprise, which is why I signed up for the peace corps(foreign aid agency of the US govt in case you're international). 2 years later I'm so glad I did it, experience of a lifetime and so many takeaways. My first glance thoughts on your situation are:
1-Just my opinion but if you are really looking to work on a project where you can make a real impact, you should probably commit to something for at least 6 months to a year, especially if the project involves any language-learning on your part. If you just do something for a couple months that will scream 'Im just doing this to build my resume'. Again just my opinion.
2-Do you think you're going to want to concentrate in social enterprise for your MBA?
3-Are you looking to do something entirely different from your background? For example I'm in social enterprise, but I do a lot of IT work as part of my position. You may be able to get more done quicker that way.
All and all I guess my main point is that when it comes to post-college / pre-MBA, a lot of people, especially bright ones like yourself want to say 'alright I want to finish this project by age XX, become a manager by age XX, and have my MBA by age XX', and I assure you that the more you get into social enterprise the more you'll realize that these int'l projects don't move on anything like a US schedule, you can't be in a hurry. But if that's ok by you, I think you are definitely on the right track. After all, there's so much time to work a typical US office job if you ever want to go back to it.
Feel free to PM me if you want to chat more in depth.