there are some decepticons that could be made is a complementary scheme. you can buy transfomers sticker from cobrasticker.com sister site reprolabels.com. i typically use these on most of my cars as small, personal upgrades to most of my autoscales.
i've attached some pictures.
the renault has the real working rub symbol on the roof.
the asc box insert was a labor of love. it was a long learning process. if you look closely, i actually cropped out the figure and overlayed it over a slightly blurred copy of the same image. this the image some depth to it.
i have not found any decal sets that offer the full compliment of livery decoration. you can find martini logos, etc. but not the full package.