If you have not yet listened to David B. Hart’s recent lecture on apokatastasis, you might want to do so. Basically he argues from the metaphysical position of Origen and Gregory of Nyssa: goo.gl/Az4jhT. He believes that the salvation of all is the only genuine solution to the problem of evil.
I thoroughly agree with him. With universalism, the problem of evil evaporates. Without universalism, the problem of evil is insoluble.
I don’t see it. The problem of evil—the fact that God could prevent the atrocities that continue to take place usually does nothing to prevent them, as well as the natural disasters that kill and maim many people—remains. In my opinion, Hart’s paper, deep and philosophical as it is, did not solve the problem of evil—unless we presume that the end justifies the means, that is, in this case that God “allows” all of these atrocities in order to bring about His magnificent goal of the reconciliation of all things to Himself, and that these atrocities and natural disasters are NECESSARY to bring about this goal, that God could bring it about in no other way.