Large polygonal traces

The screenshot I posted from the 1975 Elektor board has the same style as your power supply board?

Is this just for this one board, or are you planning to do more similar projects in the future?

If it was just for this one board, the best approach is probably to scan the board with a flatbed scanner and put it in a graphical drawing program and then clean it up a bit:

  • Put pins of components on a grid to correct for deformities.
  • Enhance contrast.
  • Retrace from pixel to vector format.
  • Maybe use svg2shenzhen to turn the artwork into a PCB to make Gerbers.

If you’re planning on multiple projects, then a script approach seems more appropriate.
A general search gets results for the magic word “Voronoi”, such as the openvoronoi project.

ferdymercury has been working on a
Zuken CR-5000 to KiCad converter

In his importer he makes much use of zones. In the thread below you can sample a KiCad PCB he made this way.