I just thought I'd drop a reply because I know how good it is to hear feedback on your projects.
Personally I think this is a great job. I love black metal and this is particularly to my liking.
The bass guitar seems high in the mix, but not to a bad degree. I guess that's just my personal preferences coming in. Basically this song sounds finished and professional (low-fi and brutal) in my opinion, which is a compliment.
I don't mind the snare being a little back in the mix for blast beats. It sounds realistic. You hear real drummers playing lighter when blasting at fast speeds (unless they use triggers) then every hit is basically at 100% volume. For this music, I think real drums sound best so it is a good mix.
As far as the other comment talking about the drums being 'out of time', I don't think it's muc hto worry about. I am a professional drummer, you could say, and I can hear the slight sloppiness, which I think is what they were referring to. But there is no actual out of time bits. This sounds like an old enthroned recording. Real drummer playing really well ---- but not quantised and metronomed to perfection. I like it; I guess you do too which is why it sounds this way.
keep it up.
I am just beginning to get myself to the stage you are at. So it is inspiring to hear the finished product is achievable.