Interesting song; certainly a "hard driving number." I listened to it several times both on a set of home-quality speakers and on a fairly good set of stereo headphones. Since you are looking for ideas to improve future mixes, I'll tell you the one issue which strikes me in the song: I hear several instances of clipping, mainly when the high cymbal strike coincides with the "attack" at the beginning of a word. Of course, I know that distortion in the guitar part is probably "part and parcel" for this type of music; but I mention one particular point in the song For reference. There were several bars in the middle of the song where the high cymbals did not sound. At the point where the words "Oh yeah," and a high cymbal strike occur on the "Oh," I hear a slight bit of clipping of the cymbal. In my mind, it gives the effect of a slight "raspy" sound to the cymbal rather than a pure, clear tone which the cymbal produces on much of the cymbal strikes. This minor flaw wouldn't "doom" the song as far as its being enjoyed; I would guess that many folk wouldn't notice the slight bit of clipping here and there. For that matter, I have heard some commercially-produced rock songs in which more clipping can be heard than that which is present on your recording. I understand, of course, that in mastering a song, one goal is to get the highest level possible without distortion; but if I were working on this project and heard what you have, I would probably want to reduce the level on the high cymbal or change its EQ just enough to prevent any clipping when it is struck. Again, if I were working on the song, I might even lower the level of the whole mix just enough to keep the cymbal strikes from driving the equipment slightly into the clipping range. As I write this from only what I hear, and having no access to the visual meters on equipment, I have wondered at times if a very slight amount of occasional clipping will show on the record meter. Having said all that, it is still a matter of what kind of sound you want overall. Had your song not come up in Mixing Clinic, I perhaps would not have mentioned it; there may also be persons here who don't agree with what I have pointed out. So at day's end, it is your call on the matter.