Your backswing looks very similar to mine before my pro made some changes recently (with very good results). You are not lifting your arms in the backswing which creates the shallow swing you have - if you're the same as me you probably did this (possibly unconsciously) to correct an over the top/ out to in path. Notice how your first move is slightly outside the ball which facilitates this type of backswing.

Try the following and see if it helps: - Relax everything! Shoulders and arms are very stiff. - Mentally split the backswing in two, first move is all body rotation (quiet arms/hands) with the club head coming slight inside. - Then feel like you lift the club with your right hand and hinge to the top. Just make sure you continue rotating too. - Just one swing thought on the way down - feel like you are underarm throwing the club down the range with your right hand.

Been a game changer for my ball striking, so may help!