Hey dude,
Fret had it right, the timing on this is spot on as far as I can tell.
There's a million things you can do to any mix to make it awesome. I'm no expert but I've learned some pretty decent practices.
First up you have to think about a complete track as a range of frequencies going on at once. When things get crowded in the same frequency it gets muddy and sounds crud. What we want is clarity, so part of the mixing process is giving things their space.
I read a random blog post where the guy went from bottom to top with a rough outline like (Kick drum (60-100hz) Bass Drum (100hz-250) Floor Tom (xxhz-yyhz) and so on). This is why when you first start mixing you tweak the levels like crazy for ages but without doing things properly it'll never sound right.
I always double track rhythm guitars and pan one track 100% left and the other 100% right, this sounds like a 50/50 mix or something.
If I have a solo or some lead riff that I only want on one track I'll record it on one track dead centre and use some sort of "stereo spread" effect to give it something extra.
Most of the lead riffs I do are ambient high delay sort of things ontop of chugs so to give them their own space I'll drop I'll generally drop the eq 1 or 2db around 800-1k and do a boost 2-5k.
Most of the lead riffs I do aren't super hard so I can get them dead on for 2 takes. So I double track and do an 80% pan left for one and 80% pan for right (the 80% thing probably does nothing but I do it anyway).
Bus/route all of the guitar tracks to one track and add compression onto that. I generally add some sort of eq to this track with ALL guitars. The on the lead tracks I'll boost the highs
ADD COMPRESSION TO ALL OF THESE:
Kick drum
I generally boost EQ at 80hz a couple of db depending on taste/sample. To make things sit in the mix I drop 95-120hz by a couple db so the bass can live there. I would also give it a small boost around 600hz-1k but it depends on the sample you're using. Low end is for feeling/thump, high end is for clicky sound.
Snare drum
Add reverb (this makes it cut through so sick). Don't go nuts though cause it'll sound horrible. I think roughly you'd be using 8-12% wet reverb on the plugin.
Bass guitar
Drop db at 80hz for kick and boost around 90-120. Play around boosting at 600-1k and see what sounds good.
My figures could be well off, it's just a guide.... but hopefully it gives you insight on it.
If you google/youtube "Metal Mixes" I'm sure you'd get way better info than what I've written, but it's a start
Good luck man,