melody, harmony, and rhythm [...] timbre
You are missing the fifth and most important: meaning!To be fair meaning is extra-musical, and varies between listeners.
Other than that, you are absolutely correct: timber is the focus of modern electronic music. All previous genres simply lacked the instruments to do much of interest in the way of timber.
Aphex Twin didn't really catch my ear, but Tipper sure did. Listening to his albums, I found myself completely enveloped in his immaculately sculpted aural biomes. When I closed my eyes, I could almost see the grumbling synth rivers, the shimmering vibrato branches, the chirping electric crickets. It was sublime in the classic sense of the word.
I would be disappointed if someone listened to Peripherals[1] or Gulch[2] and still came away thinking that electronic music was repetitive and boring!
(I bring this up because I think Aphex Twin is in a similar orbit of masterful sound design, though his style is too dissonant for my ear.)
[1]: https://soundcloud.com/tippermusic/2-peripherals
[2]: https://soundcloud.com/tippermusic/gulch-teaser