from what i've read and heard (my dads been in the air force all my life) you have just as good a shot as becoming a pilot through afrotc as you do goin to the academy. depends who you talk to but i wouldn't worry about it.
and a degree in aerospace isn't necessary. doesn't have to relate to flight if you don't want it. just something technical...actually i read recently about a pilot who graduated with a degree in art (was the best pilot in his class lol) so i'm not even sure...