The overall tonality of this mix presented me with a few obstacles in terms of evaluating it, simply because it's very strong in the 3-4kHz zone and also quite heavily mid-scooped with rather too much HF 'zing' for these ears. Although the 3-4kHz region is important for a sense of upfront-ness and aggression in this mix, it's very easy to tip the scales and end up with a timbre that's rather shouty and fatiguing. In particular, this region makes it difficult to turn up the listening volume, and this is the kind of music that I'd want to be able to turn up good and loud, even while making allowances for the lower playback levels typical of mass-market listening.
Although both kick and snare punch through the texture well, the snare attack is making my ears bleed a bit! I'd try to tame that spike a little for the sake of children and small animals.
It's partly just a question of the level of the transient, but also because the spike really hits the 3-6kHz region hard. The overheads feel like they could be higher in the mix for me, but more compressed to keep them from getting out of control during the thrashier sections. The low tom has the usual fundamental-frequency balance issue, but you probably only need quick EQ notch to sort that out. The main thing with the drums, though, is that they don't really seem to blend. Compression and short reverb are the two main tools I'd use to tackle this, although the general EQ overhaul I'd suggest in the light of the large-scale tonal issues will probably also make an impact too.
On a subjective level I do like a lot of your guitar sounds, and although it's tricky to comment on their frequency balance given the over-bright timbre of the whole mix, it seems to me that they're fairly well controlled in terms of not turning too abrasive in the mid-section. As in some of the other mixes so far, I think you could afford to leave a bit more low end in the guitar sounds, so that they do have some real power as well as clarity. However, my impressions may be being skewed by the level of the bass guitar, which does seems to be lacking a certain amount of low end -- it comes across fine on the small speaker (which is good), but feels a bit small on my nearfields.
The vocal in the verse sounds fairly respectable once the mix timbre is compensated for, but I found the lip noise in verse 2 a bit distracting. The chorus comes across as more brittle, though, and the 4kHz region of the sibilance feels overbearing despite what sounds like some de-essing going on. I think the vocal is probably too high in the balance as well most of the time, which risks belittling the backing track by comparison.
I love the way you've popped those backing vocals into the mid-section -- very clever to spot that they work so nicely there, although the tuning could perhaps be a little tighter. The downside, though, is that you don't leave yourself much in the way of ammunition to make the final chorus entry stand out, so you could see this as something of an 'own goal' in context. Shame, though, because I do like it, and it gives that long double mid-section stretch a definite additional shot of momentum. In general, the BVs could also be more heavily compressed, because they're not at all stable in the balance at the moment, and I think that's dissauding you from turning them up enough in the choruses.
Switching to mono presents this mix with some difficulties, as the wide-panned guitars take a big step down in mono, the overheads lose top end, and the chorus vocals appear to lose some important body. In terms of priorities, I'd therefore put addressing this issue up there with an EQ rethink at the top of the list.
Thanks for submitting this mix. The good news here is that I think that if you can iron out the main large-scale mix-timbre and mono-compatibility issues, a lot of the smaller points may cease to be much of an issue.