I've seen some, but you are right, there isn't much. Buuut I also can't blame people for not making more. XDD Hell the only reason I like the idea is because of the POV series! I think it's a great idea in the context of that story, but outside POV meh...
Well i feel discord could have a good enough power to manipulate stuff during that particular episode where screw ball was shown o.o it's like a warped reality so i dont see why not. After all its discord logic xD
They all start out so innocent. And then you see them years later and you wonder 'WHAT THE HECK WENT WRONG?!'
Characters like Diamond Tiara of course aren't meant to be so much 'characters' are obstacles for the protagonists to overcome. And as such can't have character development since this would contradict their function in service to the plot.