Do they see surveillance coming in ... anytime soon?
Nobody had any idea about when surveillance would appear. The floor suggested many years, CASA said it might only be a couple, "you never know".
What was their reasoning for bringing in the Broadcast requirement ... when they, presumably, decided standard E wouldn't work?
That's it. D was not acceptable because it unduly restricted VFR entry to area. The floor told CASA that there was hardly any overflyers at Broome, and so D would not realistically inconvenience anyone and be a darn lot simpler. It wasn't stated, but it was obvious that CASA believes standard non-surveilled E is not safe enough and that VFR traffic had to be "known" to the system via radio to raise the safety level enough. It was also mentioned that E had the transponder requirement: I got the distinct impression that CASA is relying on this as a mitigator. They also imply as much in OAR's written response to submissions made to the original March proposal. The floor then suggested that transponders be required in D to achieve the same aim.
Why didn't they just go to D or C?
VFR Access.
Very disappointing.