Nice bold move with the verse vocal, giving it an immediately intriguing telephonic mix sound with obvious delay/reverb special effects. However, I'd query the decision to pan it so far to the left, because anyone listening to just one side (people in a lot of small restaurants/shops, people sharing earbuds, people with defective audio hardware, to mention just a few) will lose quite a lot of intelligibility as a result. Even were this not a concern, I'd suggest if anything panning the vocal to the right, rather than the left, simply because otherwise both the vocal and guitar are panned to the same side, making the overall soundstage left-heavy. The extreme vocal panning in the chorus is fine, given that the two leads are balanced, but the BVs feel too dry, and are too easily confused with the leads for me. Also, if you're going to wide-pan like this, it's probably best to edit the vocal timing of the two leads to match more closely -- there's some distracting stereo ricochet on some of the consonants in particular.
Widening the bass in this mix is not a bad tactic (it's something that the famous rock mixer Andy Wallace often does, for example), but in doing so you've introduce phase mismatch at the low end of the mix. This can lead to low-frequency inconsistencies in mono, or in stereo systems that use a single subwoofer, so is best avoided. Try simply high-pass filtering the widener effect's return at 100Hz or so -- you'll still get the width, but without the risk of bass problems.
Just by nature of the fairly wet overall mix sound, most things are already blending quite well, but the snare in particular could do with some further blending effect in addition to the longer reverb, so that it sits with the rest of the kit. I'd instinctively go for a shorter stereo ambience, and probably restrict its stereo width a little to try to match the overheads image. The lead vocals in the chorus also feel a bit too separated -- upfront's alright, but if they're going to be as loud as this in the balance (and panned as they are), I think they do need a little bit more blend to really belong with everything else. The toms seem a bit over-resonant and overpowering. Maybe a bit of automation might help here to keep the balance more consistent if you like that level of those mics for their spill contributions.
Love the idea of a transition effect before the second chorus, although the execution of it doesn't quite feel on the money yet. Perhaps its the right-heavy imaging of it, or the way the following snare feels a little bit thin, I don't know. It's very difficult to judge what exactly will smooth it out without tinkering with it directly in the project. It might be that you need to let the transition effect go to the kick, rather than the snare, even though I do like the general concept of stopping it on the snare -- it gives that upbeat a kind of extra psychological power.
Serious props to you for being the first person to run with the idea of adding something new to that final chorus entry, and it doesn't half make a difference! It's certainly the most successful take on this particular long-term dynamics challenge so far. (The transition there is also part of the recipe, but again it feels like it needs a bit more tweaking before it really delivers properly. Those things can often be pigs to nail!) That said, the specifics of what you've added could probably be managed more successfully. The first thing that bugs me is that you've effectively added a seventh to the first chord in the process, which seems to destabilise the harmony significantly, making it seem less powerful. The second thing I'd say is that the sound feels a bit too sustained and synth-pad-like to me (although I suspect it's guitar -- it's pretty well buried so it's hard for me to tell), and something which is matched a bit more to the existing bass or guitar rhythms would probably reinforce the band's original intent more effectively. Finally, the additions are bunched mostly into the centre of the stereo picture, which narrows it and also muffles the drum details a bit much for my liking. (It also clutters up the vocal range quite a bit, despite the wide vocal panning.) Adding pads (synth or otherwise) at the mix is almost always most successul if you very carefully target them to specific frequency ranges.
I found the stereo image very appealing, and the stereo treatments also assist with the blend to some extent. However, mono-compatibility is a bit suspect, and both the cymbals and guitars seem to lose a lot of treble in the conversion to mono. Overall tonality isn't bad at the frequency extremes, but the general mix warmth (and the bass guitar balance in particular) seem to suffer from a bit of a spectral dip in the midrange, particularly at 350Hz or so. I'm not a huge fan of this frequency range myself, because it's the most common place for muddiness to reside in a mix. However, you do need enough going on there if you're going to avoid things sounding brittle, especially in the abrasiveness 'danger zone' during the middle-sections of this mix.
Well done for trail-blazing so many valuable new ideas! All grist to the mill...