Luck is always going to play a large part in how your life turns out. I didn't have the perfect ROTC life.

I was a History major with good grades (3.5 gpa), my ROTC commander tried to get me kicked out (really long story), I almost lost my pilot slot, I sucked at the PFT, but was a good cadet. I had, luckily, a Major that went to bat for me and saw in me the ability to be a good pilot.

I was naive enough to put my future in the hands of luck, but it worked out. Going on 6 years flying and have loved (the flying part) every second of it.

If you want more of a guarentee then go find a Reserve or Guard unit that you'd like to fly for and have them send you to pilot training.

Good luck with your decision