[eru]

I don't understand why a self-model would be necessary for free will?

> [...] c) its decisions are for the most part determined by physically internal factors (as opposed as external constraints or publicly available information).

I don't think humans reach that threshold. Though it depends a lot on how you define things.

But as far as I can tell, most of my second-to-second decisions are very much coloured by the fact that we have gravity and an atmosphere at comfortable temperatures (external factors), and if you changed that all of a sudden, I would decide and behave very differently.

> It's tempting to add a threshold of complexity, but I don't think there's any objectively correct way to define one.

Your homunculus is one hell of a complexity threshold.