In highlight 2 he dropped his arm a bit before the throw and I have noticed that a couple of times in clips. He keeps his arm up most of the time so that slight hitch should be easy to coach out of him.
I really liked that he moved the RB to pick up the blitzer in the 4th highlight. That to me showed understanding of the game. Of course as a high school RB the kid failed to get the middle pressure going outside and never really blocking anyone. Still Corral did a nice job of rolling away from pressure too.