Eh. Honestly, I think Sunset is more developed than you give her credit for. Also, just because she seemingly has moved past her insecurities doesn’t mean she probably still isn’t suffering from them. I would know from experience.
You see though, as much as I don’t care for Starlight as well, at least when she reformed, she still maintained some of her negative traits. Sunset did not. Whatever it was that caused her to believe that she was above everyone else, that caused her to want to exact revenge on her homeworld for being for being forced into exile, that caused her to be so insanely power-hungry, she lost it instantly. That just does not feel like a natural change of heart at all.
You brought up insecurities and anger issues, but she moved past her insecurities in Rainbow Rocks, and her anger issues in Friendship Games. As of Legend of Everfree, she does not have a single flaw to her name.
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