I thought it would be a good idea to create a new lossless comparison document.Big "Yay!", but someone needs to kick the FLAC executives into motion on getting your improvements into the official release.
(On the other hand, a test conducted by a FLAC contributor but biased against FLAC from taking on board every other codec's updates but the incoming FLAC improvements ... at least none of the competition should whine then.)
I am stuck in the industrial corner of the electronic genres (uh, Kraftwerk and Skinny Puppy and Laibach and half the Cold Meat Industry catalog ... actually a lot of darkwave need not be "electronic" as such, some use real fiddles and horns atop the synths) and certain eras (Tangerine Dream, more Kraftwerk) so this will not be more than "consider this" - where at least I try not to push my faves all the time:
* Laibach: LaiBachKunstderFuge. Yep, Bach. But deliberately done on computers, "since the work is very much based on mathematic algorithms". Laibach has darker releases, and more upbeat too, but this is a bit special in that it is (allegedly) overwhelmingly digitally generated. https://www.laibach.org/discography/laibachkunstderfuge/ FLACs to 728, not that dense music. And it saves my selection from being, uh, so last century.
* Skinny Puppy. Likely, VIVIsectVI is the album more considered a landmark in the genre of then-considered-ugly industry. Drum machine and lots of samples - the latter is kinda both a pro and a contra if one is interested in synthetic-created waveforms. Sounds like this: https://www.youtube.com/watch?v=qtySNoe0gMw FLACs to 930, that is quite dense.
* The Cold Meat Industry label was a subgenre by itself in the nineties, but it might just be my pet subgenre of synth music. They used extensively the pesky CD pre-emphasis thing - which could be an idea in itself to include in the corpus, but not too much of it. Maybe In Slaughter Natives for the dark ambient genre. Maybe you could pick their label sampler. I can get you a copy of either.
* Klaus Schulze: maybe pick Dig It for being (as the title puns at) his first fully digital recording. (Edit: bad argument - digital recording isn't the same as electronic music. But it fits a corner of the genre too, as well as Schulze starting to use more digital synths.)
* Biosphere: Substrata (although a track from the predecessor might be more familiar for its appearance in Levi's commercials). In the cold minimalist ambient direction it is a classic. See the couple of links at https://en.wikipedia.org/wiki/Substrata_(album)#Reception
... those links also lead to proposals of Brian Eno and Aphex Twin. Hard to argue against those, but:
* But while Ambient vol. 1 - Music for Airports is an obvious choice if you want Brian Eno to be represented, and/or if you want ambient to be represented - but it has so much acoustic instrument content that ...?
* Maybe Aphex Twin's Selected Ambient Works 85-92 over the successor? Only because I have proposed beat-less ambient already https://en.wikipedia.org/wiki/Selected_Ambient_Works_85%E2%80%9392
* Something by Art of Noise? Early Fairlight CMI-created (digital domain!) music, that's why.
* Björk: Vespertine? Hard to argue against her relevance (and ... there wasn't enough post-2k and not enough female vox on my list ... ?) - but here I am maybe taking an artist I like, who turned to electronic music ...
Though when it comes to Biosphere, part of me wants Biosphere/Deathprod: "Nordheim Transformed", doing the music of Arne Nordheim. Killing more birds with one stone.
Then, not what you asked about, but ...
You list a CD table, but then to make it more relevant (at the cost of time & effort, and for the second item: at the risk of lending credibility to the marketing of useless end-user formats):
* High resolution?
There is more available by now. (Also there is much more available for free.)