But why? Introducing once extinct species would disrupt the existing ecological balance and the conditions that made them extinct to begin with would continue to persist and they would simply go extinct again.
In my country, idiotic victorians introduced several predator species (stoats, weasels etc.) back around the turn of the last century - a mere blink of the eye ago in ecological time.
Since then, these species are steadily killing off our native birds species. Balance has not yet been reached, if by that we mean the extinction of those remaining species.
Many very committed people work very hard on removing the introduced predators, and restoring the conditions that allowed the native species to thrive. I think we'll win, because technology.
It is a little aggressive, but I like the case you imply for using CRISPR gene drives to wipe out invasive species. Just getting rats out of New Zealand would be a tremendous win.
For example, if humanity does something dumb that accidentally makes bees or whales go extinct, having an undo to bring back keystone species that entire ecosystems depend on is pretty nice.