With invasives there is no balance, just look what happened to the island tortoises in the pacific. Introduced animals outcompete them and rendered most of them extinct. The same would have happened to the Galapagos tortoise had they not managed to eradicate the introduced rats that were eating the young.
Also, as an indigenous decendant, I can tell you that this wasn't exactly a great outcome, but it happened a long time ago and it's too late to do much about it... it might not be too late to do something about the pythons.