Another scenario “What if ..?”
 
Honestly I see this theory with very little chance of being done, but I love the theories in the series that have little chance of happening.
 
What if Cozy Glow is actually Screwball in disguise? or is it just equal to her?
 
In fact we only see Screwball when Discord attacked Equestria, but now that Discord is a “Good Guy”, I don’t think we’ll see Screwball again, at least Screwball wants to become an independent pony and wants to become a villain or just wants to make chaos, just because she’s bored.
 
In addition to that the little pony sometimes looks a bit suspicious and it seems that very calculating.
 
And possibly she will reform at the end … we already know the story.
 
Also, it would be incredible to have another draconequus at school.