There's a popluar argument that the Fall is really a good thing overall, because it opens the door for the Incarnation of the Second Person, which Plantinga has endorsed. I don't buy this at all. Interestingly enough, C. S. Lewis's Perelandra a rebuttal to that that theory. As I recall the story, the Un-Man, who is Weston's Body taken over by the Bent Eldil (in other words Satan), uses felix culpa type arguments to persaude the Green Lady (the Venusian Eve) to fall. (It will really do good for you to fall, in fact, it will do so much good that God Himself, in the Second Person, actually came to the Third Planet).
We do have goods that arose as as response to the Fall, involving the Incarnation, but we do not have a basis for comparing what did happen to what would have happened had there been no Fall.
If God had the power to actualize a world in which everyone freely does what is right, it seems reasonably evident that He should have done so. Unless universalism is true, it would have saved a lot of people from eternal damnation. Of course, I don't think God had the power to actualize such a world, because if God guarantees that everyone freely does what is right, then significant freedom is missing.