Looks good. You are progressing, which is great.
Next step is to improve calf (specifically the soleus) flexibility that way you can push your knees further forward.
I noticed in the final video that your feet seem to rock: ie. As you bring the weight down you lift your toes off the floor. Try to keep your foot flat, with the weight evenly spread out between the heel and the mid/forefoot. By gaining calf flexibility and equal wieght distribution in the foot, you'll be able to push your knees further forward (while keeping proper weight distribution on the foot), allowing you to go deeper while still maintaining an upright position.
Br