UPDATED: 18 March 2019 - External display adapters that actually work with this model (and Arch Linux) added.
For various reasons, I found that I had a need to upgrade Windbringer's hardware very recently. This might be the first time that a catastrophic failure of some kind was not involved, so it's kind of a weird feeling to have two laptops side by side, one in process and one to do research as snags cropped up. This time around I bought a Dell XPS 15 Touch (9570) - I was expecting things to be substantially the same, but this did not seem to be the case. Some things that I found myself ignoring because I had no use for them aren't in this newer model, and some things have changed as technology has advanced rather a lot in the last five years.
As before, first I'll post the hardware specs, and then follow up with everything I had to tinker with to get working as well as how I went about it. As usual, I went with 64-bit Arch Linux (2019.02 installation build).