I think I’ve been made aware of this argument before, that God allowed us to sin in order to raise us to something better.
I just don’t believe it though… evil has no reason to exist, otherwise it would not truly be evil.
I don’t believe that we are going to be made better than we were in the garden. Perfection by definition cannot be improved upon. We will only reach our prior perfection, the perfect and everlasting joy which was always His will for us in beginning and in the end, we do not grow, we are not improved upon, if we could then we should never find a perfect state, because it therefore doesn’t exist (ie. there is always something better than what we have, always something lacking about this supposed state of original perfection).
I agree with St. Paul, but not with Aquinas or Leo. Grace needs to abound in order to free us from sin when sin has abounded, but how can grace take us to a state which is better than perfection? It restores us to that state which is lacking in nothing, I think their interpretation is mistaken.
Think about it… if Adam and Eve had been lacking in something which came later, how could it have been perfect or a paradise? If they did, then by definition it could not have been because it was lacking in something important and therefore imperfect. It would have required something else, it would be yet to be perfect.
God knows the whole of human history. He knows every action we take before we take it, He knows every sin we commit before we commit it, and He even knows who will befriend or reject His Son before He even created them (hence the ‘book of life’ which has existed from the beginning of time).
God knew that Adam and Eve would sin against Him before He created them, before He had placed them in the garden, before He even told them not to eat of the tree, He knew that they would sin. He knew that He would have to send His Son as our Redeemer before He told Adam not to eat of the fruit of the tree. If Adam was not going to chose to eat of it, He would have known that as well, and He would also know that He therefore did not have to send His Son as our Redeemer.
My theory: Adam and Eve could have known Jesus and have had all the things which have been given to us now, and therefore been lacking in nothing, but they chose to sin against God and therefore, with God’s foresight, did not yet come to have those things; which he nevertheless would have offered to them had they not have sinned.
We created sin and the knowledge of it, He didn’t. He never told us we were naked, we did. It is from us in cooperation with the angels (the bad ones that is) who have decided that there exists such a thing as good and evil. God has a will which is all good, but He does not judge those who do not do it. But everyone has judged Him, and rejected His will which is good, and therefore in compliance with this knowledge of ours that there is a good and there is an evil, He sent us laws, prophets, revelation and most especially His Son, as proof of our own guilt by this knowledge we have illegally attained.
‘Stop judging and you will not be judged’, 'the Rod with which you measure shall be measured to you, ‘do unto others as you would have them do unto you, this is the law and the prophets’
It is by our own judgment, our own knowlegde, our own doings that we are judged. If we did not know good and evil, we could not know ourselves to be naked, and therefore where is sin?
If we found nothing wrong with God, God would find nothing wrong with us. If we turned aside from our ways and found that He had done nothing wrong (ie. repented), He would turn His face back to us and found that we He had done nothing wrong as well (ie. our sin will no longer be remembered). We have created sin and the knowledge of it, and He has taken those judgements with which we have rejected Him in the garden and proven ourselves guilty of them a thousand times over.
If you disagree, please feel free to challenge this.
The problem is, that we experience events in succession, so we write of them as though they were successive - & to us they are; but it is not clear that God “experiences” them in this way. God is unknowable unless revealed - & that point is not revealed.
Sin does violence to the universe, because it is an attempt to make the universe revolve around man, instead of around Christ. It’s a sort of cosmic rape. 
IOW - those things don’t, & can’t, & never could, have the last word: it is always God who has the Last Word, because His Word is the Living Word through Whom He created the universe, & Who is “God-with-us”.