I've been struggling to keep my torso upright in the squat/snatch/clean. During the descent of each of these movements my chest goes forward which causes the bar to be way out in front of my toes at the bottom position. The worst of all the movements is the back squat, but is clearly present in the snatch video I've attached. I think this is also what is causing my lumbar to round at the bottom of these movements (hard to see in the video, but trust me it's there), but I also struggle keeping a neutral lumbar during the setup. In the video I have the bar on plates as this is the only way I can get close to decent setup. The weight in the video is very light, yet I still can't recover after my chest drifts forward.
To combat this I have been strengthening my upper and lower back, glutes, and abs. Also, I have been relentlessly working on thoracic, chest and hip mobility. I haven't made any progress in 4-5 months (it's actually been getting worse) so I thought maybe someone could chime in and give their opinion. Thanks.