So, basically done here. Alignment on the keycaps is a little bit all over the place, but only a single batch of nine truly got away from me (YUIOPASDF). Still, the quality of the laser transfer itself is good enough (so far) that I'm encouraged enough to look into making a proper jig. I will probably test that by remaking the worst keys from this batch, yet overall the board is very usable. It's a bit of a chonk compared to what I usually like, but that was expected with the materials chosen. Overall, for dedicated purchases for this board specifically, I'm in for about $16 on switches, $18 on keycaps, $8 for the hardboard, $5 (shipped) for the MCU, and $2 for the screws. Everything else was kind of already around as part of my supplies inventory.
The low-end materials show, no two ways about it, as does my inexperience with my laser, but this has come together in a very promising way, and I'm not disappointed in the looks, to be honest. In particular, I like the feel of the layout. It's kind of like having the keyboard from a 15" gaming laptop, but full travel and mechanical. I was lucky enough to notice that my keycap set came with three dished indicator keys before lasering, so F, J, and numpad 5 are all appropriate, if you care about such things; I also added a tiny drop of Bondic UV-curing resin to the down arrow after I took the pictures.
So, I may update this thread with revised keycaps when I ge the improved jig put together, but calling this one complete.