As far as I can see in that video, the squats look very good. Depth looks great.
I cant see your low back at the bottom and its hard to tell if your knees are in good position or not though.
Try shooting from two angles - side so we can see what your back looks like in the hole (turn the camera a little to the left from this last video), and front or back (front>back if you can do that) so we can see your knee positions.
The standing ab wheel is impressive. I cant do that, but I do have ~75 lbs of bw on you