I vaguely recall a cost-benefit (cum safety?) analysis being carried out a few years ago in Tasmania in relation to non-radar Class E, my recollection is that it used the methodology of a Tobago getting a rather close look at a burner.
Mitigators? - I think there were a couple of (subsequent) mitigators. One could have been E airspace being mitigated back to Class C, and the other was a strangely coincident mitigation of a "relocatable" radar down to Tasland. Scuttlebut had it the latter was the fastest go-to-whoa radar commissioning in the history of Australian ATS.
In that individual case.
Avalon - won`t go there, but I suspect because the location is notionally in a "surveillance" environment, etc, etc...don`t forget TCAS...
Broome and Karratha - probably will get away with E over D without too many near-heart attacks. There is (was?) a suggestion for the E steps to remain active outside TWR hours, not exactly sure as to the rationale there - a convoluted perception of CTA "protection" through E steps for IFR is the only inane thing I can remotely think of.
Just for the hell of it - Alice - E over D - not going there at all
2c inserted