in all honesty, i cant fault the form at all (at least from the front) do you have any side views?? slight hesitation just before lockout, maybe try some heavy rack pulls (just build a platform to put the plates on) also just make sure your shoulder blades are absolutely pinned in place and it should help on lockout, as against getting the bar to 1" before locking then having to roll then back into place.
TBH thats exactly how i lift. like looking into a mirror
if you want to work you hams hard also, then use a 4"platform to stand on whilst deadlifting. pull the bar from the floor to lockout as normal, but lower the bar down the front of your thighs (keep a slight bend at the knee) to the floor and the work your hams get is astounding. id keep that exercise as a higher rep one, remember its an 'exercise' not a 'lift'
keep goin, doin very well
are you a competitive powerlifter? and if not, why not