I got some suggestions, from one death metal head to another. Have you given it any thought about using amp sims and cab impulses? I love them personally. Your choice but, definitely remember less can and is always more. As for the drums, don't mess with them. I know you want to but don't, they are pretty much pre mixed, maybe just a hair of compression on the kick to bring it out alittle. As for guitars, don't scoop so much mids out, roll the gain down, double track, and quad track, but be tight. Pan guitars fully to the left and right, bass in the center, did you even have a bass track? Use distortion on bass, brings the metal guitars to life. High pass filter around 125 hz, and low pass at around 9.5 khz for guitars, bass I normally high pass at 60 hz, and low pass at 600 hz. Just give that a try, see how you like the results. I can help you out more if you need it. Here is a little sample of something I have been working on, like I said all digital, guitars modeled, ez drummer, direct bass. Also gate the the guitars and bass, first in your channels. Well, it wouldn't let me upload it for some reason, but yeah, I am getting pretty good results these days, and we are very similar guitarists, so if you want some more help, send me a message. And definitely pay attention to what the guys say on here, they can definitely help. Just remember you don't have to follow all of it, mixing is suppose to be fun and a learning experience so live and learn bro, keep chugging.