Too much drums
I think that this particular piece has just too much of the metal drums - not all metal has the frantic pace of the drums. Listen to some Iron Maiden and see how they get the blend right, without drowning out the guitars and the vocals.
While I'm not exactly a fan of this type of vocals, it did work quite well - the timing may have been a little out, but in the sort of Heavy Metal that you've chosen, I don't think anyone really cares about timing, just thrashing as hard as they can and getting the crowd whipped into a frenzy.
Perhaps a little refining work could be done to make the track sound better, but in the end it's down to the author's choice.
[Review Request Club]