New big update! After cleaning up the blueprint I could finally go back to adding new features, and I started by adding my favorite one: Hex grids!
There are still a few minor issues that need to be ironed out (the viewport doesn’t handle hex grid snapping by default, for example), but for the most part everything that works with square grids now also works with hex grids. Adding hex support was easier then what I had feared, but then I had designed the system to be mostly grid agnostic from the start.