Well done, although I would ask that you only include those images that you modified/created, instead of every image. When extracting the folder, they would then replace the files in the existing package, so no need to download more than there already is.
This is not only to better manage credit on the files, but also for future convenience. In a future update of the module, it will be possible to use substitute (modded) packages. They would be loaded before the built-in ones (falling back to original if not present), and would be in a separate folder, so you wouldn't need to replace any existing files. It will also be possible to provide mods of .pal files.