Looking back Ansett had the monopoly in the Nth west .May be wrong but Qantas only did Karratha/pt Hedland and Broome.
Then Hammersley Iron got a contract with Qantas which was great as we had Paraburdoo to Perth flights direct instead of flying all over the Nth West.Most flights i went on hardly had any passengers.
BHP--Newman and Hedland still dealt through Ansett ,and Qantas wasnt getting much bussiness in Pt Hedland ,so pulled out.
Then Ansett went belly up so Qantas had to service all the places.
As far as the Nth west is concerned,i think one airline is enough,maybe with the exception of karratha.
Thers still plenty of opportunities down south--Exmouth ,Carnarvon,Geraldton,Perth run a good possibility for a large plane.
The rest of the state is up for grabs and if Skywest mapped some good route plans i cant see why they cant make a $.
As far as fly in/fly out goes,well,thats up to who can get a contract