I think she has very good mechanics. However as stated before her arm circle is off. This will cause arms problems in the future. Ideally you would like the arm to go over the the nose as a point to look for as a catcher to ensure the arm is in correct plain. This will keep the rotator cuff in the ideal circular motion and not cause soreness or possible harm to the cuff. Also make sure there is a little bend in the elbow to maintain the flexibility in the arm. Good luck in her future endeavors.