With the new addition of filters to photomode, I think some selective color filters would be a nice addition for stylizing photos Idk if this is even possible but it'd be cool to have a color of your choice to stand out (for instance if you want the tailights to stand out the most, you could use red, or if you want the body color to be the focus, you could use whatever color it is)
this seems a lot more complex than anything they currently have in the photomode. id suggest just getting gimp or photoshop, you can edit your images like that very easily.