Captain on a flag carrier of a huge country with a rapidly growing economy and you’re contemplating a move to Perth as an F/O on a second tier carrier? I think you’re nuts.
If my recollection is correct, the status afforded to Air India captains is that of a demigod. You will greatly miss the respect afforded to you if you choose to work in Australia.
Lastly, unless you have extended family in Perth, who will look after your young children if both you and your wife are working? Obviously, as Australian citizens, you’d be well aware that having full time live in domestic staff is unheard of here.
Not sure if the clean air and great beaches of Perth makes up for any of that.