Hi. Eliezer, very interesting post - I have been thinking along the same lines against epiphenomenalism, though I don't think the point is as clear as you thought.
"(2) It's misleading to say it's "miraculous" (on the property dualist view) that our qualia line up so neatly with the physical world. There's a natural law which guarantees this, after all. So it's no more miraculous than any other logically contingent nomic necessity (e.g. the constants in our physical laws). That is, it's "miraculous" in the same sense that it's "miraculous" that our universe is fit to support life. Atheists and other opponents of fine-tuning arguments are not usually so troubled by this kind of alleged 'miracle'."
Actually the fine tuning of physical laws to support life is a big deal. Pretty much the only way to explain it is that there are a large variety of physical universes with different laws, so it's not improbable that some would support life, and (by anthropic selection) we'd be in one of those.
The fine tuning of the hypothesized qualia bridge laws would likewise need an explanation. If there are a wide variety of bridge laws, does anthropic selection explain why ours are fine tuned to make our qualia the same as our mathematically describable brains would say they are? It seems evident that it does not - we could have very odd qualia yet still be conscious. So it would indeed be a strange coincidence to say the least.
To me it would be an even stranger coincidence if 'qualia-properties' need not logically exist, but do exist in nature, which happen to be just like the qualia that material beings would (falsely) say they have.
I don't think that is the case; I think that it's much more likely that either we are material and material beings must be on to something when they think that they have qualia, or that we are not on to something when we think we have them, or some middle ground between the two (we are are material and have some kind of qualia but they are not what we think they are).