Looks like an interesting list of topics.
I wanted to add:
If we presumed that morality were simply an evolutionary adaptation or a law of nature, how is it that morality is then seen to "evolve" (more like change, "evolve" is wrapped up in common speech with the baggage of "progress" while true evolution is merely change that happens to survive through generation) from one century to another, one culture to another, and even within one culture? It's not something purely biological. So one could speculate that we were "born with" certain ideas, but then we can't just turn around and say we are free to change them on a whim and say it's bogus. It would be really great if more people from the internet world could take serious courses in philosophy.
The basis of everything in the human mind is philosophy, so if we start second guessing that, we have nothing. We can't "know" anything and might as well assume our actions are completely determined, even if our common sense and everything else points to the opposite. I'd say we're part of nature, but we also have free choice, however limited that might be by our finite information and powers, the influence of others, etc.
Religion and philosophy are closely tied with one another. Simply getting rid of the idea of a "God" and assigning the origins of morality to philosophy doesn't really get you very far, because you still have to account for where philosophy comes from and what it means (if we're simply biologically determined, it's just something quirky about our species but ultimately meaningless).