Well, first of all, there is no such place as Fairbairn air force base. RAAF Base Fairbairn closed down years ago. Its now just a domestic airport with a RAAF squadron located on the other side of the terminal to ferry VIPs around.
When the article says the Super Hornet will fill any capability gap that the F-111 leaves behind, it definitely cannot be referring to either the speed, range or payload of the F-111. I don't think there is any aircraft of the same size that can fill this gap as a modern airframe. The Super Hornet falls well short in this area, and I, too, am totally surprised that the Super Bug was chosen - at such short notice no less! The C-17 Globemaster III acquisition I can kind of understand, but this just doesn't make sense.
The F-16 was always a better aircraft than the F/A-18, but the only reason the Bug was chosen back then was because Australia was looking at using them on a carrier they planned to get from the Royal Navy. Then the Falklands War made the British think twice about getting rid of one of their flat-tops. Now that Australia has pretty much finalised their choice of design for the two new amphibious assault carriers, landing a Super Bug on one of them is out of the question. The RAAF would be better off getting the latest block F-16 instead. Better yet, push to get the F-22. Forget a strike capability, and balance it with the best fighter available.
The RAAF has no dedicated Electronic Warfare platform for the Growler to replace. I seriously doubt the RAAF will ever get the Growler, so that can be passed off as mere speculation. The Wedgetail is the airframe the RAAF will be utilising to cover that role.
And lastly, Carlo Kopp is probably the last person I would listen to for advice about what to do with the F-111s. His solution of making a few alterations to keep the F-111s well into the next decade are laughable. I won't give his recommendations much credibility.