I can't offer much in the way of experience with this type of music, either, but my ears and musical mind were telling me that there was something missing. The only thing I can relate it to is possibly something totally and completely different, but I'll take the risk.
I recently listened to a song by Beneath The Massacre, and was pretty intrigued at the choices made in the mix. The snare is all but completely buried, the high-end of the drums was also buried, yet the kick seemed to be smashing my face in an all-out assault. The guitars dominated the sound stage by a large margin.
Here's the song I listened to
I hate that sound. I makes no musical sense whatsoever - yet... People seem to somehow connect to it.
The sound that I can connect to is most of what Testament records. I don't really *like* their music, per-say, but it connects with me on some level.
Here's an example of (what may or may not be) a similar music style, but drastically different mixing methods.
Wow... I've digressed a lot. Not entirely sure where I was going with all that... But..
Your mix sounded much different than either of those. Guitars sounded really fizzy, and the drums sounded too organic / natural to me. I don't know of any metal that has natural-sounding drums (again, apply salt liberally, I don't usually listen to this type of music). Metal drums seem to be processed to the hilt, usually.
It's always interesting hearing different people's take on different musical styles.
I should press delete on this comment, but I'm gonna press submit instead.

(shoots himself in the head with a big rubber bullet)