I am proposing to implement vector layers in the GIMP, as I find that they are a necessary asset in CG artwork, and it would be great not to have to keep switching in between the GIMP and Inkscape all the time, manually re-rasterizing/exporting/loading the vector elements each time you want to change them. The vector layers will contain shapes made up of paths. Whenever a relevant path is changed, the vector layer will automatically re-rasterize.