This is primarily for Iain17 so I'll address him if the rest of you don't mind...

Well, I put your ideas to somebody who likes to think about these kinds of things.

The gist of what I suggested was:
If God is perfect, then we as His creations must be exactly as He intended. In this case, our actions are pre-set, and any sins are what He intended.
I think this is pretty close to what your point was, if there's abig difference that isn't covered by their response I'm sure you'll point it out

Their response:
This is an interesting take on the poe. So I'm guessing their arguing "so you could say God sinned". They are starting off with an incorrect theology. There are different approaches to the question "Does God know and do all things". Some have said God does not know and do all things, they are taking the extreme at the other side and saying it is God doing all things. There is the middle knowledge approach that is taken by Ockham and Molina (and William Lane Craig, more recently). God knows all possible 'free choices' of all free creatures in all possible situations and in all possible worlds. He cannot be surprised, but what actual choice gets made is still the creature's actual choice.

Allow me to give an anology that expresses my theology of creation and God's will.

A man (God) puts a child (man) inside a room (garden of eden). The man put's a piece of candy (tree of knowledge of good and evil) in the room. The man knows that if the child it's it he will get sick. -----

This is where theology diverges. The atheists are saying "God made/forced us to eat the fruit...it is God who sinned." which is incorrect. Let us continue:

The man knows that if the child eats the fruit he will get sick (sin enters world) and the man knows the child loves candy and will eat the candy. BUT if the man doesn't give put the candy in the room then the man isn't giving the child free will to do what he wants.-----

If God didn't give us the fruit and the free will to decide for ourselves, then God would have forced us to worship and love him, which is simply wrong. Even though God desperately didn't want us to eat the fruit, if he didn't give us the free will, then it would basically be slavery and we would all be robots.

Yet God knew in advance that since we were going to eat the fruit, he had the "paramedics" on the phone waiting. God knew we would sin (he still allowed us the free choice), and had predestined Jesus to sacrifice himself so that we might be made perfect in God's sight.

CONCLUSION

God does not do all things, he "intended" for us to do good, by creating us in his image, but he gave us the freewill to decide for ourselves, we are making our own decisions.
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This is a large issue, I could probably get into a greater detail if needed.

I can't guarantee they got exactly the right impression of what you were proposing, but what they say is thought-provoking nonetheless. I'm not saying this is necessarily my opinion btw.

So, Iain and others, any comments? I'm sure there are one or two of you who won't be able to resist