I think you make some excellent, well balanced points, HD.
What I'd like to see is a move towards a classification that doesn't revolve around meteorological conditions. Though it's somehow intuitive that avoiding collisions is related to the ability to look out the window, our current system overrates the capability of the average pilot to see and avoid random traffic.
I'd like to see:
1) Airspace in which all traffic is separated by ATC, (participation is mandatory).
2) Airspace in which participating traffic is separated, and a separation service is always available. (current class F, and arguably the same as class E in VMC)
3) Airspace in which participating traffic is separated, and a separation service is provided on an ad hoc basis. (current class G)
even if the separation standards could be varied for different types of flight.
We'll see how class N, K, U or whatever stacks up against that.