She doesn't really push off and open her hips as much as she should. Her arm action is very good. I would think about having her do some long toss. The idea of throwing the ball higher and as far as you can will often lead to changes that happen organically, this is much better than filling her head with a bunch of directions. When I do long toss I like have an area large enough so that they can try to throw the ball as far as possible. I bring a bucket of balls and tell her to heave it as far she can, I encourage her to set a 'new record' by getting the ball she is throwing past the furthest one out there.