attempting to harmonize a marriage of philosophy and science

Probably impractical, frankly. Philosophy is philosophy. It doesn't deal in facts.

Now, there is a philosophy of science. It was an interesting class I took. How do we know a second yesterday is a second today? Stuff like that.

For example, we're visually informed of our vast quantum to cosmic environment by photons which undergo no change between emission and absorption, and thus entail no passage of time — that's how they convey information about their source. The only detectable change in photons is their wavelength; correlating with 'in transit' spacetime expansion. I put that in quotes because this redshift is the only evidence of their purported journey.

That is true.

Dark matter is proposed to account for gravitational effects that are unwarranted by observable matter in GR. Dark energy is proposed to account for otherwise theoretically inexplicable spacetime expansion.

Yes, those are hypothesized things. Could just be placeholders for something else, or could be actual matter. Dark energy is more controversial because it was first invented to account for the rate of cosmic expansion accelerating (instead of slowing down, as we expected). However, other measurements have said it isn't expanding at an ever-faster rate. I don't keep track of this, so I'm not sure the latest scholarship/studies/measurements. This was a controversy a few years ago (as all contradictory measurements are).

I'm inclined to regard the whole thing as complexifying possibilities atemporally emergent within the infinite potential of erstwhile nothingness. Emergent complexity rooted in ephemeral quarks is at once experienced as the ubiquitous becoming of individual existence and as a boundlessly evolving cosmic environment.

This is where you lose me. Perhaps it's just the phrasing. Was there ever "nothing"? How do you even define it? Physicists define it very differently from ordinary people, and know that in our present universe there is not ever nothing. Quantum fluctuations are not "nothing", for example. Even in empty space isn't really empty because of quantum fluctuations.

NOVA did an interesting program on emergent complexity several years ago. Don't recall the title. Contrary to what many creationists claim, complexity arises all on its own if conditions are right. In some cases, it falls right out of the math.

I don't believe consciousness is important to the universe at all. Our sun will die in about 5B years, and the universe will go on. There is no reason to believe it won't. The laws of physics don't appear to be dependent on us (or a consciousness).