I suppose one could operate then like a strike fighter and send an only self defence armed (weight and space) perhaps slightly larger version of the FAC along as a tanker to extend their range.While I also like the idea of cheap, highly mobile fast attack craft, the problem in the Australian context is range.
The strate of Hormuz is only 20 NMs wide.
I like any factor that that provides an adversary more diverse problems.
But to operate them in our region they would need to be forward deployed.
This in turn means local basing (with the problem of getting local permission) or some kind of depot ship or both.
And then the base or depot ship itself will become a target so must itself be defended.
Roll on the the problems of forward deployed HIMARs but on a larger scale.
Fueling both ways would offer a dramatic increase in range but with added complexity.