Nightmare Moon element of disloyalty (betrayed her own sister) / discord element of mocking (contrary to an innocent laughter) / Chrysalis elemnt of deceive (contrary to honesty, tricked everyone with her ability to change form) / Sombra element of rudness (contrary tokindness) / Sunset Shimmer a dark element of magic (contrary to Twilight who united all her friends she split them in the other world). / Still missing one more villain for the generosity element.

By the way I love this concept, looks like something that could be in a stained glass.

Element names hmmm... surley you have got many of this comments, but this is just my humble opinion.