I am not experienced, but do get coached on the O-lifts so take this however you want.
It looks pretty good from that angle. The only thing that might be a little off is the following, but you need to check for yourself cause the angle not from the side.
The shoulders should be right over the bar with arms in line with the bar when it's on the floor. As you start the first pull, the knees should be coming back so to clear a path for the bar.
You're back should stay at the same angle that it started at through out the first pull until it gets to the bottom of the knees. This is what I think you are doing on some reps: increasing the angle of the back with respect to the floor too early.
When the bar gets to below the knee and the back angle is the same, your shoulders should now be in front of the bar. The back angle should then increase as the bar passes the knees and started grazing the thighs and accelerates upward.
Hope that helps.