On the space thing, I'd expect the GTI to lose the lower boot level position as this is where the battery will go.
The R doesn't have room for it, its already got something in that hole!
The GTD? A Mk8 GTD? Looks doubtful.
If the GTE is anything to go by the fuel tank will go there. I still think GTD will have a place just with exactly the same engine you see now.