I'm using as reference an ICAO document dated Dec 2012. It lists a total of 16 civilian & 9 Military ILS installations in Australia.
The new Wagga ILS is further away from Adelaide than Melbourne by about 100nm and about 40nm further from Mildura than Melbourne. So its irrelevant to the debate.
In my experience in dealing with the airforce (for non aviation uses), they have become so restrictive, bureaucratic, insular and restrictive in the last 3 - 5 years, that I can imagine it would be easier to deal with CASA / ATSB following a landing on a highway than the airforce. It is easier for us to use military facilities in Singapore, Thailand and the US than Australia.
The only way I get to 11 ILS enroute is to include Sydney, Melbourne, and the cluster near each. The reality is that most of these are not effective alternates in situations such as this.
If you said you wanted an alternate within (say) 250nm with a different weather condition, then Adelaide's in trouble.
My real point is just that we are more precious about ILS than most other countries. From the same ICAO document, I count 147 airports with ILS in China, 53 in Japan, 23 in Malaysia (with nearly the same population), 26 in Saudi Arabia, 26 in Thailand.
If we were serious about aviation safety, we'd use the $6.4 million being spent on paint, carpet and partitions in the Mildura terminal upgrade and put ILS into 4 more airports. Or embrace WAAS. Our government is shortchanging us, and pilots end up taking the blame.