A very interesting post!
I think that, as with anything, before we discuss something we must define it. In this case, we must define "free will". I like to define it as "The ability to make your own choices."
Do we have that ability? I would say yes.

it would mean that our little demon friend can predict every decision we ever make, before we make it.
How does that fit with freedom of the will? well, it doesn’t.

Just because an omniscient being knows what choices you will make doesn't mean he makes them for you.

What it comes down to, is that free will seems to have no existence outside our subjective perception of reality, which as we all know can be quite misleading.

Is our perception of reality only subjective? I would argue that free will is an objective reality, since it can be readily observed in nature. We can see how different organisms, whether they be human or otherwise, can make their own choices and react with their environment. Humans have an added ability, the ability to reason and make choices based or not based on that reason.
Also, we have an area of the brain completely devoted to making choices. That seems to be a good indicator that we can make our own choices.

Regardless, I really enjoyed this post. Great job!