Certainly for what it's worth (like nothing) I'd be behind this. I think it'd make a fantastic addition.
However, as far as I'm aware, appropriate sprites only exist up to gen 4 pokemon, seeing as HG/SS were the last games to use the mechanic. This obviously means we'd run into problems with pokemon from gen 5 and gen 6. Maybe sprites that I don't know about exist, or maybe the people that are pretty handy with spriting could work their magic at Ame's behest but I reckon the job of recolouring all of the shiny sprites has got them busy enough at the moment.
Hopefully something can be done for this, but I won't hold my breath.