Well one of there reasons for purchasing such a long range aircrafts was to be able to connect Perth with London direct. Also theyre looking at Sydney Dallas direct.
Qantas has recently changed to 767 for Sydney Honolulu, however thats probably because of the Australian winter, the pax there will be upped come summer.
Perth J'burg, well etops would be an issue there, if the rating is 207 minutes, well they might just be ok, because I can only think of one port in between Perth and J'burg and thats atleast 7 hours from Perth.
I think theyd want to put a new aircraft on the Perth Singapore route. They currently fly 767s of which are competing against SIAs 777 which now flys 14 times a week, plus the A340 thats flys 7 times a week. I believe SIA are also intending on upping that even more to a total of 24 flights a week making Perth one of SIAs most frequently visited ports in the world. Qantas obviously needs to do something there. Perth's skys will soon be fully owned by an overseas carrier, and we cant have that. Not that I dont like SIA.
But in all seriousness, they can put a 777 on any route