You've made excellent progress in a short time, particularly your contact point and your finish. But, your set up and takeback are still suffering from old habits. I've said all this several times before, but, I also understand that acceptance preceeds change. You need to first accept the premise that your swing is generated by two techniques: (1) upper body rotation, and (2) arm supination and pronation. Ideally there should be virtually no independent swinging of the arm from the shoulder or the elbow. With your arm and racquet set, and your left hand on the throat of the racquet and the racquet head right in front of your face, you pivot until your chest and racquet face are facing 4 O'Clock. That is your takeback in its totality! Your arm and racquet have not moved. They can't because your left hand is still on the throat of the racquet. The racquet is pointing straight up and the face at 4 O'Clock (not pointing back at the back fence, and not with an open racquet face pointing to the roof). From there, you initiate your unit turn forward with your right hip and that movement causes the racquet head to drop back. But, you are still taking a high looping takeback with your arm (elbow and shoulder joints) independent of your "unit turn," and your unit turn is totally insufficient. AND, IN ORDER TO ACHIEVE AN ADEQUATE UNIT TURN YOU NEED A LOWER, WIDER STANCE. Further, you are leading your backswing with the racquet head, squandering the racquet acceleration of waiting for your forward turn to supinate and then pronate before contact, and the racquet face is open to the roof. Those three habits: (1) upright narrow stance, (2) takeback with the arm, and (3) leading the takeback with an open racquet face, are a ceiling on further improvement. IMO, if you employ a measure of discipline by keeping your left hand on the throat of the racquet until you are ready to initiate your unit turn forward, it will go a long way, if not all the way, in curing your remaining bad habits. PS: What chico says about turning your thumb downward, I interpret and pointing your racquet face back toward the back fence. I agree with that, but, don't overdo it. If you can get it to 4 O'Clock, that is sufficient, IMO. I reject the notion of purposely raising your elbow in the backswing, even a small amount. That is a slippery slope that may lead to a flying elbow which will only complicate the swing and add an unecessary variable that will impair consistent clean ball striking, and serves no useful purpose. At the completion of your unit turn, YOUR HAND should be hitting the wall behind you, not your elbow, AND NOT YOUR RACQUET HEAD. To be clear, if, at the completion of your tackback, your elbow is IN and FORWARD (where it must be at the beginning of your unit turn forward anyway), and your racquet head is STRAIGHT UP, and your arm and grip are loose and relaxed, inertia will cause the arm to supinate and the racquet head to drop down below the hand when you initiate your unit turn forward with the kinetic chain beginning with your hip rotation ala The L&R Guy. But, the success of all of that is dependent on a proper takeback and being in the correct set up position (stance, unit turn and racquet position), as I describe above, before you initiate the kinetic chain.