(1) It's not about producing subjective experience, it is about being subjective experience. The idea here is that massive, vague mereological fusions of subatomic stuff just aren't the sort of thing that can be subjective experiences. Just as no fundamental particle can be a chariot, since chariots have parts.

(2) I have no idea yet. I'm considering some sort of interactionist dualism, or some sort of idealism, or some sort of mathematical multiverse theory with self-contained mathematical structures that play the role of Platonic computations, with measure assigned by a simplicity weighting that generates the appearance of a physical world.

And of course I'm considering reductionist physicalism, reductionist mathematical multiverse theory, etc. as well. That's where the other 50% comes in.