> The same goes for GNOME, for Unity, and so on and so forth; the whole problem with Linux usability is that it's little insular islands of standardization in a sea of "whatever."
You do know that this is a generalized problem, not a Linux problem, don't you? If you use enough, diversified, Windows or OSX software, you'll see yourself in the same situation. (Yes, there are more than one toolkit to develop under Windows and under OSX and yes, they "feel" as different as Qt vs GTK...)
Anyway, get a good (Arch or Kubuntu) version of KDE4 and you have mostly any software you want, Qt/KDE-ized, and most GTK software also will look/feel nice if you use QtCurve. I personally use kubuntu + chrome + libreoffice + eclipse/poweredbypulse + lazarus + virtualbox.
> And anyway, that still doesn't solve the problem of the underlying system just being too drat complex.
Nothing solves that. Windows is VMS, the rest of us (including BeOS/Haiku, you can open a terminal and type "ls -l" there) is Unix. Operating systems are complex beasts. You see "forty years of cruft layered", I see "forty years of evolution, trial and error to solve find heuristics to unsolvable problems." It is a good thing. Every single, "younger", other-lineage OS got stuck in their growing pains by the 90s and died. Some examples: Mac OS 9 -- had to be replaced by unix, even after IBM and Apple spent some millions (billions and billions? :-D) with Taligent/Copland; Windows 95/98, son of MS/DOS, son of CP/M -- had to be replaced by VMS before the monstrosity of Windows ME broke the company; Every Single Smartphone/Palmtop/Tablet OS -- replaced by unix.