I applaud your disciplined focus on construction. I am not entirely sure about your use of the center line in the depiction of the head. Sometimes the head is clearly pointing to the side, while you still draw a center line in the middle?
A more helpful remark might be, that you can improve the upper torso by separating the ribcage from the shoulders (bones, joints, muscles) The ribcage is more egg-shaped, not much wider than the head at the neck. The square-like appearance of the upper torso comes more from integrating the clavicles and shoulders, but as they move separately from the ribcage you can easily improve your construction by separating them and the chest- and/or back muscles and shoulder joints into separate entities in your mind.