Just a few example layouts, each with a KLE json, the corresponding SCAD file, and a license, if applicable. The JD40 layout is straight out of the conversion script, but for some of the others (i.e. crkbd) I've made them a little prettier by doing stuff like connecting thumb clusters and adding standoffs. Hopefully this can give an idea of what's possible.
Note that third-party layouts included here may be subject to their own licenses/copyrights. Though it's a bit unclear whether they actually apply to any files created using them, they are included for completeness.