So she postpones the fall formals even though she wants the crown to rule in equestria, and by postponing it she prevents herself from coming back to equestria for another 30 moons, so why postponing it in the first place?
and besides.. once the principal finds out that twilight wasn't the one to destroy the fall formals, isn't she atleast tries to find who did it? or assuming that sunset shimmers did it and ban her from joining the princess competition ('cause she was the one to frame twilight)..
and how come the crown didn't have any effect on twilight's head?
i'm guessing they needed the storyline to continue :S
anyway it was a great movie