For the love of God, if you like Aviation and like the classes, and your ultimate career goal is to be a pilot, DON'T change majors. As you said in the beginning you are more motivated in school because of this. There are plenty of jobs for college educated kids with any degree down to Underwater Basketweaving. You will earn a living on the outside if you have to with an Aviation degree, even enough to go out and do an MBA on the side if you so wished...but you aren't getting into MBA school without good grades as an undergraduate, which is why you need to stay motivated by studying what you enjoy.

Prior to getting my Air Force pilot slot, I was a Financial Advisor, and got hired with an Aviation Degree and a Business minor. I was hired over some stiff from Stanford, because all they cared about was my personality and ability to interact with clients, not what I majored in, which only accounted for half of my academic career regardless. You can get any job you want if you network and interview well.