Hi Jonathan,
Sorry again for taking so long to get to your essay. At any rate, I enjoyed it and had a few comments. Regarding the cosmological theories you discuss on the second page, I think that for all theories, the question is how well they work with other theories. I look at it this way. Physics should aim to explain the world in the most complete but simplest manner possible. So it is often a balance between simpler v. more encompassing. That said, when presented with competing theories that are essentially equivalent in what they encompass, I see no reason not to go with the simpler theory.
I thought you had some excellent points to make, notably that we should not conflate simplifying assumptions with predictions and I particularly liked what you had to say about space and dimensionality (and I tend to agree - it makes little sense to talk of dimensionality in completely empty space as it has no meaning). I also agree with your point about entropy and have long tried to make the same point myself (it's interesting that you mentioned Sean Carroll's take on that since it was a bone of contention at the FQXi meeting last year, though not one captured on all the conference videos).
I'm not sure I understand, though, your comment that we should stop looking to unify the forces and start observing how nature is already unified. In my mind, those are the same things. I don't particularly agree with the current field-theoretic approach since it is largely predicated on a non-emergent spacetime, but I still think it is, to some extent, "observational" (string theory being the potential exception).
My only other criticism is that I'm not sure I saw a convergence of your ideas to a single answer to the posed essay question. Rather it seemed more of a general critique of how science operates. While valid, I wonder if it wasn't a bit too general.
Anyway, nice essay though.
Cheers,
Ian