Your leg drive could be more efficient. Your butt is coming up off of the bench which is easy to do when your heels are not on the ground. Your legs need to push up the bench and into your shoulder to keep the arch stable. Getting your heels on the ground could help. If that doesn't feel comfortable, either way, try to push your toes through you shoes and drive horizontally up the bench rather than vertically up.
A bit of elbows flaring out on the way up. Keep the elbows on the south side of the bar so your forearms stay slightly angle back to lockout position.