I only watched the first video, but some quick thoughts. First, it's a solid start. Overall it looks good. Your weight moves forward on the feet a little too much too soon - you do a good job of keeping your knees back and staying over the bar, but as you're doing that (as the bar reaches around mid-thigh), you lean into the bar rather than staying over the heels and bringing the bar back to you.
could finish a little more aggressively at the top, esp w regard to leg drive. that will allow you to move your feet better - get them disconnected from the floor and replace them flat-footed in your squat position. now they're getting a bit stuck, and with your weight moving forward already, your stance turns out too much and your;re on the balls of your feet in the squat. when you move the feet, think of driving the heels down and slightly forward into the floor.
you're hesitating a bit at the top of the pull before you start moving under. once you're extended, be done extending - get your feet moving and pull under the bar immediately.
when you pull under, you have to pull under the bar - that is, don't just drop into a squat, pull the bar to your shoulders and bring your shoulders up into the bar- you're dropping out from under it and it's crashing onto your shoulders. this is hard enough to contend with, but with your weight already being forward, it makes it even worse. finish the turnover completely (i.e. get the elbows up and the bar secure on your shoulders) as high and as fast as possible and then ride it down into the bottom rather than throwing the bar up and then trying to catch it in the bottom of the squat.