I have never had any experience in operating Metros so I cannot comment on their economics. As a passenger they are not the most attractive, having the unfortunate experience of using them to regional destinations.
What the issue I can comment on though is, what the passenger wants. I have extensive knowledge of regional Australia through both family connections and business and I am very confident in expressing what they want.
1 Affordable airfares (cheap???)
2 Cheaper still Airfares
3 safety perception ( a problem with low cost)
4 creature comforts.
put a cabin class up against a metro at the same price then they will go with it. Charge a little more and they will drive.
Sydney - parkes $90 1 way, ok. $150 50% will drive, $225 and 90% will drive. There is not a lot of disposable income in many regional areas.