My response to 70kg Squat Clean:
Positioning from the start looks pretty good…from the video angle, it looks like you’re sitting back pretty far, I would even try to raise your hips just a few more inches up and allow your shoulders to start a little further over the bar.
Not sure if it’s just these two videos, but looks like you’re sitting far back in the squat too, which is placing you into a awkward bottom position. In the full squats you’ll needs your shins to travel forward (tried to add still pic but it didn’t seem to work).
For the 100kg squat clean, I believe if you work on these 4 points:
First pull positioning
Upper back strength
Your lifts should look significantly better…that with time/reps it’ll come together just keep at it. On the plus side, you have a natural feel for the bar, which doesn’t come easily for most Weightlifters.
As for the ratio for a beginner question. I wouldn’t worry about it, just focus on getting reps under the bar and focusing on the tasks mentioned above for now. Positioning will be key for you, eventually that will be a limiting factor in squats as you increase in strength.
At least those are my quick thoughts based off of 3 videos…