Currently listening to DT12 now. I didn't want to start a new thread...
This album has way too hot of a mix, and the sound is a little hollow to me. This was the first DT release where I was disappointed on release and first couple of listens. This album basically destroyed my overall interest in Dream Theater and modern prog overall, and I have (and still do) felt that prog from established or semi-established acts from the 90s and 2000s have been putting out sub-par music since 2012, with rare exception.
As for the tunes, I view this album in 3 parts.
First third: Opening instrumental til Enigma Machine. Classic moments throughout, but a little too technical for technical's sake, one thing that MP rarely let happen were odd time stuff that sounds choppy and lacks flow, like anyone can come up with crazy odd time sections on a MIDI program on the computer, DT just have a drummer that can handle that stuff. The Looking Glass is a great song, even if the Rush inspired main riff sounds choppy and should have been in 4/4 or worked on a little more to make it seem more interesting. Overall the tune is classic DT, the rest of the tunes have their moments but could have used more time and work, The Enemy Inside is fine, but the main key/guitar melody could have been worked on more as well to be more complete.
Second third: The Bigger Picture to Along For The Ride. Although I think TBP might be the strongest single song on the album, it feels similar in 'sound' to the remainder of the album, a sound that is prevalent on all the Mangini-era albums, and I don't feel like any songs in this part of the album has their own identity. There's a lot of good ideas here, but nothing connects to me, seems like a bunch of B-sides surrounded by stronger material.
Final third: Illumination Theory. I'm listening to this and typing in real time. Opening reminds me of Haken. The driving riff is cool, one of the best parts of the song. A lot of this reminds me of late-2000s DT. Hmm.. more Haken sounding stuff. Verses remind me of one of something of FII, can't place it, I think it's Just Let Me Breathe. Chorus goes back into that 'sound' I described in the previous paragraph. Some instrumental passage. Goes into the ambient section with hints of world music. I like this part, it's serene, and flows out of the previous riffage well. I've always felt this section and the next don't really belong with the rest of the epic... Over time, I guess I've grown accustomed to it. The orchestral section is beautiful, and has made me shed a tear once or twice, the live version sure did. I think more could have been done with it, or perhaps its role in the entire epic could have bee worked on, but the section itself is pretty much perfect, I kinda wish it lasted longer.
And then in come that BASS. Then the rest of the band comes in and it's like "oh, right, I forgot I was listening to a Dream Theater song." Maybe that's a good thing sometimes, but as I said, it's like they added that ambient/orchestral sections in between the main piece. All this riffage suddenly is making me question what the point of all the beautiful parts were for? Holy cow, though, some of this instrumental stuff is crazy. I like that part at 13:56ish before Jordan's keyboard solo. His solo is standard Rudess era DT stuff. The riff underneath is the one from the beginning of the song, and it's cool, but the road to get from there to here just seems like patch work to me. Climax is alright, seems a bit underwhelming, could have used more build up to it, but it may also because it's drenched in that Mangini era DT sound, I don't know how to describe it, it's James' processed vocals, the chord progressions, etc... The outro is classic similar to the ending of Octavarium. Overall, I think the band should have had masters of 20-30 minute epics like Neal Morse or Roine Stolt in the studio to help them put IT together.
I've always felt like the Easter Egg at the end is one of the best moments of the Mangini era, and of course, way too brief. Need more of this. Just jam off this stuff guys. Of course it makes the track length fake news-y because IT is really a 19 minute epic... I never liked "hidden tracks".
So in all, more enjoyable than The Astonishing for me, but I still rank it low on my DT album rankings, like 2nd or 3rd to last, even with IT on the album. Too many criticisms that I can't get over.