I like the creative bits you added - nice.
There are some fairly fundamental frequency balance issues, though. There are two areas of the frequency spectrum where it sounds too much has been pulled out of everything - In the low mids/lows broadly centred around 130hz, and in the mids broadly centred around 630 hz. This has the effect of causing the mix to lack warmth and fullness.
The guitars also sound like they are overly boosted in the 2-3k range, so the mix is fatiguing in that area, and the guitars are fighting for frequency space with the vocals. For example: Listen to that opening verse with the muted high string guitar lick and compare your mix to the released version. Notice how in the released version, the guitar riff never competes with the vocal, even though the vocal is relatively low in level, whereas in your mix, the vocal “comes & goes” as it competes with the guitar riff. This is mainly down to the way you have eq’d the guitar riff to be really present in those critical vocal frequencies.
Possibly what I think may be happening is a result of being too zealous in pulling lows and low mids out of the sources. Particularly if you’re getting material that is tracked really well, you may find that you don’t have to do as much subtractive eq as you would on a song tracked in a home studio.
This may be related, but drum-wise, I’m hearing a lot of attack from the hits of the drums - which is good - but the actual tone and character of the drum shells seems to have been really reduced. Sometimes room mics can be helpful to bring that stuff out. Leaving a little more of that shell tone in the drum kit by being less zealous about sucking out mids and low mids with eq will also have the effect of lending the mix more warmth and fatness.
One more thing: This may sound like a small thing, but it’s bound to be brought up if you have pros critiquing your mix - Leaving empty space at the beginning of your mix render is Mix Mistake #1. Your mix should start immediately when the play button is pressed, not 5 seconds later. “Top & Tail” your mix as if you were sending it out to a client to listen to. All the attention to detail you may have put into your mix can be blown away before the mix even starts if that detail isn’t taken care of. LOL.
Congrats on getting through such a mammoth project! I’d hate to have to be the dudes who have to listen to hundreds of different versions of a 10 minute long song in the URM academy!