Raise/spread the chest.
Keep the elbows up.
Push the head back, not up, on the ascent.
Push the knees out in the hole, don't let them track forward when you reverse the movement.
Keep the arch/tight hamstrings in the hole, utilize the bounce and this will help keep the knees from tracking forward at the bottom.
Looks pretty good, though, just add weight, eat steak, rinse, repeat, be awesome.