Hey this is a pretty cool take. As the lads have said, you need to gain some stamina for the down picking sections because there's times where you get left behind the beat, especially during the single note riffing at the beginning.
I made a simple lesson to work through for stamina building, have a go at that for a week or so and see how you get on:
http://www.guitarmasterclass.net/ls/Stamin...-2-Downpicking/You could devise your own riff progression to work with but the idea is mixing rests in with work so that you don't get fatigued quickly and you can continue working at higher tempos.
Try to be more consistent with palm muting as well, for example at 0:30 you lose the chunk of the palm muting.
Apart from those areas you're quite solid !