Also, this show seems to lack any form of rank and file or any form of organizational structure in either the "good guys" or the villains.
The villains either operate solely as individuals or as wild swarms like in the case of the Changelings. The Storm King was as close as the series got to an external imperialistic threat to Equestria. It would have been more interesting if there's an Evil Pony based empire that attacked Equestria. I do think that WAS originally intended for the movies, judging from some internal leaks, the COSMOS leak, that came to light awhile back. But was scrapped.