As for "electronic" music that isn't really a genre (maybe it was when it first (?) made the hit lists with Switched-On Bach, but that is more than fifty years ago), then for the purposes of a comparison, one may want to
* cover the genres and styles people may want to compress (probably with more EDM and contemporary hip-hop)
* cover various signals to see if that makes for a difference.
The first is not unimportant, but it does not classify the way you are asking.
The sorting you are using on the other genres often is a bit "in increasing denseness", and a similar sorting for electronic genres would be from minimalist to Merzbow. (I see that you are putting Merzbow different, and I kinda disagree here: this kind of noise music is electronic - and *the* CD with a specific trait is the audiobook!) And for a "denseness" rough sort, you might just see how many bits LAME V0 thinks is adequate?
But a couple of other dimensions:
Percussive or not? You got music that is beat-less and you have music dominated by percussion - and percs that are notorious killer samplers for lossies (Prodigy's "Fighter Beat" got infamous on HA ... the version you are listing got this (bonus) track?).
Vocal-oriented or not? The instrumentation might still dominate the need for bits, but if the music is an acoustic-recorded signal with instrumentation accompanying it ... that is something else at least "by ear"
Indeed, how much is "recorded in free air" is a classification in itself, only it isn't that obvious to know. As you mention it sounds a bit artificial (like, cooked up for some constructed purpose), but I think it is a point.
So I suggested the Biosphere for being the chill, non-dense, non-percussive corner of the spectrum - maybe you should find some even more minimalist; some synth industrial for being a missing style (quite dense some of it), Laibach's take on Kunst der Fuge for being instrumental "electronic-only" and apparently not having used a microphone, and I forgot about this techno classic https://www.discogs.com/release/3144862-U-96-Das-Boot - but even if the Laibach (and Prodigy) got released way into the y2k's, my suggestion list is likely too heavy on "mom and dad's plastic disc collection", and too little of that neo-rave that the music industry rebranded as "EDM" to distinguish it from what parents did - and you seriously need a major hip-hop producer to belt out some beats from the hard drive.
Oh, and one suggestion: while your diagrams are pretty clear on what compresses fastER and slowER, a novice won't necessarily be able to relate it to ... I guess one benchmark is MP3. Suggestion: a vertical bar (as to not mix size into it) that indicates speed of LAME default 128 CBR? And/or maybe an AAC if there is a "canonical" encoder choice.