Could do a few routes with the ATRs from Melbourne. Devonport, MT Gambier, Mildura, Albury, Wagga, Woolongong even Canberra. Could open a MEL Base with 3 a/c when enough are at the SYD and BNE bases first which seems the priority. How about a PER and ADL base i.e. for Olympic dam etc.
VA already struggles with loads out of Mildura on the jet, the prop will not suddenly attract masses more. Devonport council was considering to shut down the airport due to low passenger numbers and the short drive to Launceston. QLink in Devonport still offer marketing drives with low fares to attract enough load, this is despite being the sole operator there. Gambier loads to Melbourne have never been huge, OConnors struggled to fill a 20 seater consistantly and the conquest was used for most runs. Most passengers are on the Adelaide track due to it being a SA town. Wagga and Albury are similar to Gambier with the main loads moving towards their respective state capitals. I would guess the average load factors for the 30 seaters would be around 60%.
Woolongong, Canberra and Launceston are already serviced by turboprop and jet traffic. Melbourne - Woolongong would be a bit of a long haul effort at ATR speeds, especially return into a strong westerly.