Josh,
I will try it one more time ---- G through A are not ascending levels of safety.
Do a bit of basic study on the subject, don't take anything here as gospel, satisfy yourself. Eurocontrol ( for those who are so anti-US that they will not even consider what happens in the US) publish some quite good background material, they also publish their design risk levels in various airspace, and follow up by publishing assessed achieved levels v. the design levels.
With the appropriate addition of services as traffic/traffic mix increases, the intent of ICAO airspace classifications is that any category of airspace, correctly serviced, is equally safe.
As I have said, time and again, the separation assurance standard is the same in each classification, and it is so high that adding additional resources does not "increase safety". The risk level remains the same, just the system costs increase --- classical economic waste.
One of the major problems in Australia, when we moved to "alphabet soup airspace", was that there was no genuine attempt at real reform to take advantage of the new design principles. We just gave our existing "controlled/uncontrolled" airspace names that were close to the new classifications. In short, the miss-allocation of resources continued. Only now are we going to adopt real Class D for non-radar towers, instead of the "D that wasn't D" we have operated for years.
I just love the claim about "the paradox of E" ---- claims made by (I very strongly suspect) alleged pilots or ATC who have little, if any, experience outside of Australia. All they know is what they don't know they don't like.
Only in Australia (and then only in the minds of a few people) is E a "paradox", or regarded as in any way controversial. For any body who has done any serious international aviating, E is extremely difficult, if not impossible, to avoid. Outside of Australian, nobody gives a toss about E, they just get on with the job.
But, the "little Australians" know it doesn't/won't work.
The real issue is the resistance to any change in the aviation scene in Australia, at a great cost to the Australian industry as a whole. In many ways it is part of the legacy of the "two airline" era, where "cost plus" ruled, and silly pilot demands (like E/Os on B767) were just lumped on the ticket costs. I don't find it at all surprising that both the airline of the "two airline policy" era, no longer exist.
From memory, there have been about five investigations into Australian airspace management over the last twenty years or so, conducted by highly qualified and respected bodies, such as UK NATS, Roake Manor Research (Siemans), and of course the FAA, there are more, but each one has made essentially the same recommendations, that we should adopt the intent of the "new" ( but its been around for years, now) ICAO approach to CNS/ATM, to ensure that assets are properly allocated, not something we do now.
Given the proven traffic handling capacity of the US system, and also given that it produces the best air safety outcomes, is it surprising that US NAS is the basic starting point for Australia?? ----- but not if the recalcitrants, the little Australian, get their way.
Tootle pip!!