Interesting and wordy read.
I've been jotting down a few ideas on how to 'evolve' an OS. I've come to the conclusion that you should write an OS that adapts itself to the way you think. Something forgiving for 'dumb' users. Something complex for 'smart' users. It should remain ubiquitous.
I shall keep the rest of my ideas secret so I can become a patent troll. lol
The problem with the concept of a perfect OS is that perfect in this case is very individual. To this day I consider BeOS to be about the closest to perfection I ever came across (though I have to say I did miss Magellen's configurability in some respects verses Trackers relative simplicity). However, I knew it's faults (and there were some hum dingers in there) and developers dispised it for the most part because it forced them to work in a threaded way, regardless of whether or not the application needed it.