The worst written scene in all of FIM is Vice Principal Luna interrogating Twilight in her office. Luna bought into "evidence" of photos that were clearly cut out and glued together. The whole scene has no tension, because it lasted barely over a minute. Flash's moment of intervention could've been removed in favor of the Mane Six or Luna not falling for that stupid trick. It's so broken, it turned the first film into a colossal failure, and nothing after would save it.

But my most hated part of all of FIM occurs during the climax. Sunset Shimmer was presented as the mean-girl, alpha-bitch stereotype and turned into a she-demon from a Diabolous Ex Machina, and then the EoH are acted by a Deus Ex Machina. The EoH defeat Sunset Shimmer…and completely destroy her character.

Sometimes we can get tired of redemption stories in the show, and part of it is twofold. One for the villains not being well-written, the other for having the redemption story be poorly done. Redemption stories by themselves, though, aren't bad or good. You need the execution to be good to make it satisfying.

Including the IDW comics, Sunset Shimmer's redemption is the second-worst in ALL of Friendship Is Magic. Worse than Sombra from Siege of The Crystal Empire. Worse than Discord. Worse than Luna/Nightmare Moon. They're better than Sunset's. One exception is Radiant Hope from Siege, because she's a complete Mary Sue, lured in villains to sabotage the Empire, and watched others get hurt and killed all for the goal of reviving Sombra without a shred of guilt.

The one big problem with Sunset's redemption and the idea of me thinking of forgiving her is the fact that the Sunset seen in EQG1's resolution, Rainbow Rocks, the Holiday Special, the shorts, and Friendship Games isn't Sunset Shimmer. What we see in the films is the Elements of Harmony replacing her original personality with a brainwashed version of her. This is how the Elements want Sunset to be. This is the Elements influencing Sunset's psyche and development through a personality they created.

Sure, she has the same memories, clothes, hair, and voice. But there's more to a character than those. The mannerisms and natural development from villain to protagonist matter, too. Sunset never had that. She never had that moment where she actually chose to change for the better. She didn't decide during the climax that she was going to try and make things up. The EoH's version of Sunset is the one doing all the redemption for her. As a result:

1. Her whole redemption lacks any conviction. The scripts try to tell the viewer that Sunset is the one who caused it, and she's the one who can change it. But how can Sunset change it when the real Sunset doesn't even exist anymore?
2. The quality of Rainbow Rocks and Friendship Games worsens. Each of their plots is partially about Sunset's redemption and spreading her wisdom to others. But neither acknowledge how Sunset became the way she is. They acknowledge her defeat, but that's it. In fact, both films flimsily hide her complete character change.
   

Villain!Sunset is flatter than Flash, but the current Sunset is completely fake by how forced her transformation and development are.

Sunset's current personality has factually way more dimension than the prior. There's no denying that. And there are reasons why she is popular. But when it comes to something like a magical lobotomy, I don't care if Villain!Sunset was a stereotype. If I want to see Sunset redeemed, I want to see Sunset redeemed, not a brainwashed figure in her place. To this day, it's my most hated aspect of the spinoff. What the EoH did was so evil that Equestria Girls hasn't recovered from that scene. Until they settle it once and for all rather than treat her redemption as something she chose throughout, it won't.

The way she changed is similar to Nightmare Moon's defeat and change back to Luna. But even the first film screws it up. Princess Luna grew so jealous of Celestia that she turned herself into a completely different pony. Nightmare Moon is Luna, but Luna isn't NMM. The EoH relaxed her anger, bitterness, and jealousy and reverted her to the Luna of old.

Now, contrast Sunset's with Starlight Glimmer. Unlike Sunset, Starlight is the best villain this show's ever had. Rather than re-write about her, I'll quote my analysis:

Undoubtedly, Starlight Glimmer's a fraud. By not conforming to the very same messages she claims to celebrate (not sacrificing her cutie mark while forcing everyone else to do so), she becomes a major hypocrite. However, don't let that mean her beliefs lack any level of sincerity. As a character, she's incredibly sharp with a sense of how she can be one step ahead of the others. With the ReMane Five locked up, she manipulated FS into trying to out her accomplices. Even more, Starlight doesn't act like some magical being who reigned in terror æons ago. She's a unicorn with very strong magical powers, and we have no idea what her past is. There's no doubt that her lack of past is intentional; it makes her feel both relatable and real.

 

Unlike the other villains, she does believe in the magic of friendship, but not the MoF that the others believe. Instead, she sees the concept of individuality as a hindrance of both growth and triumph. Her idea of the cutie mark doesn't translate to being someone of equal potential, but how you must conform to Equestrian matriarchy/patriarchy. By telling everyone to give it up, force them, and hammer it in, she's making them believe that her totalitarian opinions will lead to an eventual Equestrian revolution. Not "revolution" as in warfare, but "revolution" as in how a new ideal of Equestria can be legitimately established. Even after she was revealed to be a hypocrite, she never relented that belief. Consequently, this further legitimizes her gray opinions on Equestrian society.

 

Starlight Glimmer is a very credible, three-dimensional villain. She has very legitimate motives that back up continuity from not just the whole series, but also Magical Mystery Cure. One big problem from that finale is how it conveniently changes the whole definition of the cutie mark from being something you innately like and look forward to for the rest of your life to how it's forced upon you. Starlight Glimmer — and the two-parter's theme itself — openly critiques the very structure and magic of the cutie mark. Surprisingly, SG's political assessments and critiques of the cutie mark system not only opens up further discussion and history of the cutie mark, but it also closes the continuity gap that Magical Mystery Cure opened. Her angst over the cutie mark isn't plucked out of thin air. It's an ongoing discussion in the fandom, including Pinkie Pride itself. There's legitimate backing to it, and she has very good reasons to tell passersby to abandon the practice. By being a very slick motivational speaker, Starlight Glimmer becomes both imposing and very threatening.

A lot of people focus on the what and the time (the latter being an okay reason) and not the why. Take a look at why The Cutie Re-Mark showed she became the way she was and focus on obvious details.

1. Starlight and Sunburst were blank flanks, and the episode pins down that he was her only friend at the time.
2. When Sunburst saved Starlight from the book collapsing on her, he got his cutie mark. His friends and family celebrated, and they never saw each other again. In what was supposed to be one of the best days of Sunburst's life, Starlight lost someone she cared for most.
    
   Now, on a more complete scale, does that sound rather petty? Yes. Even Starlight admitted it by saying "he moved on, and I didn't." She knows it's a petty feeling, but the event that etched deep in her subconscious triggered anger for cutie marks and the thought that if it happened to her, she won't let that happen to anyone else so they don't feel the same pain.
3. She never blamed him. Each time this event was addressed, she always blamed his mark, not him. Sunburst was an equal to Starlight, but when he got it, he was seen as the really special pony in her town. To her, he achieved a much higher status, while she was still stuck there. Those things don't go away, especially when you're a kid.
    
   Unlike Sunset, who wallowed that she never found another way even as a teen/adult mare, Sunburst was sent off to Canterlot while Starlight was still a foal. Kids are impressionable, and what may look like simple, petty feelings to us as adults can leave a lasting impact on kids. It doesn't matter if she talked with her family or not. If this kind of event created a trauma trigger as a kid, talking to parents won't go away so easily.
   

In short, cutie marks and the idea that the cutie mark = someone may be more special or better reminded her of that event. Their cutie marks are trauma triggers, and they can be just about anything. That's why she created Our Town and repressed others' talents. She believed by repressing others' talents, everyone will be on equal level, and she'd create true friendship and true harmony. Unlike the other three-dimensional villain Discord (who willingly manipulated the Mane Six), Starlight truly believed she was doing the right thing. But when she was outed and her entire world crumbled, Starlight became angry, desperate, and hungry for revenge. If she lost her comfort and her home, then Twilight will suffer, too.

Why Twilight?

1. She led her friends to Our Town. As the Princess of Friendship, she bears similar responsibilities to Cadance, Luna, and Celestia even on a lower level. Alicorn princesses have a lot of weight in their words and ideology. Current Equestrian canon relies on the princesses' decisions, because they affect everyone else around them. She has a higher class status.
2. Twilight Sparkle tried to figure out a plan to free the townsponies from Starlight's totalitarianism. Focus on the scene outside Sugar Belle's bakery. She kept her friends in check when they were arguing and pointed her head at Double Diamond. Secondly, while they were all locked inside Starlight's jail, they had to come up with a plan. Twilight was the one who helped lead the idea of Fluttershy being the one to find clues and defeat Starlight, for she was the one who bought into them. 'Shy outed her, but Twilight helped plan the ruse.
   

Even when Twilight told Starlight that her interrupting the Rainboom, Starlight didn't believe her, accusing her of lying and being egotistical. This indicates not that she doesn't care, but in reality is completely unaware of the consequences.

But what changed and started her path to redemption are three things:

1. Starlight being extremely startled by the wasteland. Observe by how said that there's nothing here.
2. This expression:
   
    
   Remember why "show, don't tell" is lauded. By showing reactions and details, vivid images embed subconsciously. The clearer the image, the more impactful. That image was the mark of when her ascension began. And it was here where the audience truly realizes that what see saw from Starlight as evil isn't what Starlight thought as evil. This led to the flashback scene in her hometown followed by the climax and resolution.
3. Starlight snapping at Twilight when she hoped Starlight'd change her mind. It was one of the most literally insane soundbites I've ever heard. Starlight wasn't just fighting hard to gain revenge on Twilight. No longer did she focus on the wasteland. Literally, she lost control of her own conscience and showed a moment of fury. Starlight looked…lost.
   

Even though the climax didn't rely on lasers and topographical destruction, it was one of the tensest in this show's history. Twilight and Spike's lone path to returning the timeline to normal was stolen and on the verge of being destroyed by a unicorn trapped in her own psychological destruction. Insane fury brimmed in her eyes and bled on the parchment. The loss of her friend plus the loss of the town she helped rule ate her up, including still denying the destruction of her timeline.

There, Twilight demonstrated how far she'd come. Rather than literally fighting her, she had to convince Starlight with Twilight's own lessons she learned. Rather than take her out physically, she had to help her and convince her that this path wasn't worth it. And even if Starlight as worried that what happened with Sunburst could happen again:

Twilight Sparkle: I guess it's up to you to make sure they don't.

And after Starlight agrees to take her hoof and let the Sonic Rainboom occur, Starlight's redemption was Sunset's done correctly. Rather than forcing a redemption out of her and brainwashing her into redemption, she gave Starlight the opportunity to choose redemption. By letting her choose, you see the character's thoughts, actions, and consequences all in one go. Her redemption feels genuine.

But to make that better, becoming Twilight's protégé makes her redemption feel very satisfactory. She chose to face the consequences, but rather than force her to spend time in exile, Twilight elected to teach her so she can use her powers for good. She knew Starlight was powerful, but rather than let her go with no direction, Twilight believes her leading Starlight into doing good things will allow her to use her magic expertise and knowledge for the benefit of everyone. More importantly, it recognized one of Keep Calm's flaws, even if backhandedly: Discord was redeemed because Celestia assigned them. Celestia didn't assign Twi, Twi decided to herself.

Also, the comparison between the Equal Four and CHS is apples and oranges. The CHS were frightened of her from the start and hated her. The Equal 4 (and by extension, the rest of Our Town) didn't hate her. They felt betrayed. If the four didn't want to forgive her, who can blame them. But they believe Starlight's apology was genuine and forgave her.

For those who are curious, here's my ranking of redeemed antagonists/villains, from best to worst.

1. Diamond Tiara
2. Starlight Glimmer
3. Trixie
4. Nightmare Rarity
5. Gilda
6. Discord
7. Nightmare Moon
8. Snips & Snails (EQG)
9. King Sombra (Siege of the Crystal Empire)
10. Sunset Shimmer
11. Radiant Hope