Werbil says
"Given the above four points how is it possible for G to be safer than E?"
One could ask if E is safer than G for IFR RPT, given the VFR pilot is the lowest common denominator, we are dependant on his transponder being servicable, or switched on, their knowledge of the area and the IFR tracks. The fact that they are only required to maintain 1500m horizonontly and 1000' vertically gives a lot of time to avoid them. 1500 m = .8 nm (@ 250 Kts = a few seconds) Less time than what you are allowed for a TCAS RA.
Again the size of the zone will be interesting, to contain the instrument approaches the zone will need to be at least 15nm, others say it will be between 6 - 10 nm. It will really become a dog's breakfast if the approaches aren't contained. The report on Broome operations outlined the reason for the non standard CTAF of 30nm radius as being due to the traffic mix, and to give all the traffic time to assimilate the traffic.
Jet departures are nominally around a climb rate of 3000' fpm, which means it will be out of the D upper limit in 1 minute. So VFR aircraft operating in E around A050 - A100 on the IFR routes will get some nice close ups of the jet traffic as it hopefully passes by.
Inbound, the D controller will have the details of the IFR traffic inbound, but won't know about VFR traffic until they call up. With the number of VFR aircraft I have seen and heard in the BRM CTAF, all inbound within a few minutes of each other, the tower frequency will become easily congested, creating delays, which will further deflect the controllers role of stopping mid -airs on base or final. They can happen outside the zone) If would appear that there will need to be more than one controller on duty, which means the establishment will need many controllers. One wonders were they will come from.