While second hand ships can deliver significant advantages, i.e. a rapid increase in capability to meet changing circumstances or to plug a gap (expected or unexpected), if poorly planned can lead to block obsolescence, increase the average age and maintenance requirements / bill for the fleet and damage local industry reliant on the work on deferred replacement vessels.
Procurement of Largs Bay got us out of a hole that was caused by cost cutting on maintenance and poor planning on the replacement of the existing fleet (over estimation of the remaining life, that seemed to conveniently forget they were already old ships, two of which were bought second hand. In the time the RAN operated Success she served alongside the second hand Westralia and the modified commercial tanker Sirius, neither of which was ever as satisfactory as a second, new build tanker would have been.
I personally believe the acquisition of the four Kidd class DDGs offered to us in the mid to late 90s, or even a number of early Ticonderoga class CGs, would have been ideal. They would have provided, without modification or upgrade, substantially greater capability, at lower cost than the upgraded FFGs. Their larger crews, than the FFGs, while more expensive, would even have reduced the impact to the RANs technical manpower retention following the retirement of the Perth class DDGs and the governments short sighted cost cutting. Above all, the would have easily filled the gap between the DDGs and AWDs as well as averting the reduction in hull numbers caused by the badly run FFGUP.
The flipside is, if we had acquired the Kidds somebody in Canberra likely would have decided we could delay AWD for a decade, just deferring the problem. Had we acquired the Upholder class submarines to supplement or replace the Collins class we would have either had to spend far more to build / maintain the capability, or worse, spent the same money and had less capability as a result.