After some deliberation, I decided to customize the layout of my Planck. After all, that's a big part of what attracted me to the project in the first place.
I'd seen a few posts from other people who had issues flashing the chip from a Mac, though, so the idea was a little intimidating. I just successfully built the thing - I don't want to brick it now.
But the "Reset" key is in a really annoying default location on multiple layers. So I figured I'd give it a go and trust that I knew enough about the process to fix the keyboard if something went wrong.
Turns out, everything worked perfectly.
Here's the new layout:
I'm happy with it. It will take some getting used to, but it's logical to me.