By the time she had her final battle with Starlight Glimmer at the end of Season 5, Twilight Sparkle pretty much had already gone as far as she could as a student of friendship. It was time for the disciple to become the teacher.
Just as the show has grown past the basic principles of friendship, so has its target audience. The kids who were five when G4 premiered are now approaching their teenage years. With greater maturity comes more mature friendships and different sorts of lessons. Instead of lessons on sharing toys and slumber party etiquette, the target audience is now beginning to learn how different sorts of personalities, which should clash, can sometimes connect for deep friendships.
As explained in Starlight and Trixie: Teenage Besties for a Maturing Audience, Starlight and Trixie demonstrate how older friends can joke around in ways that would be taken as bullying or unfair for younger children. Starlight and Trixie resemble the sort of friends who could jokingly say “You’re getting fat” or “Shut up!” with no one getting their feelings hurt. The Mane Seven, by contrast, teach lessons to children who are still at the “You have to play nice” stage.
Fans have compared Starlight to Twilight, often with criticism that Twilight has too many clones (Starlight Glimmer, Sunset Shimmer). Neither of these two will be winning any awards for most original name, but their personalities are certainly very different from Twilight’s. Starlight is new and naive in the ways of friendship, just as Twilight was when she first started, but Twilight and The Mane Six were (probably) already close to adulthood during the first episode, so they can’t really explore the changing ways of friendship that come with puberty. It wouldn’t make any sense if they all suddenly started acting differently.
But Starlight, being a newbie with an entirely different circle of friends, can explore these friendships with authentic naivety.
Starlight also continues the trend of befriending those with wildly different personality types. No two ponies (or dragon) in The Mane Seven resemble each other, but they still follow a certain set of rules. A personality like Trixie’s would never fly with them. Just look what they did to Rainbow Dash.
And although they befriended Maud, most of them never really got close. The exception being Pinkie, of course. They mostly befriended Maud because she’s a friend’s sister, and although The Mane Six learned Maud was not the one who needed to change, they never really got comfortable with her. Maud confirmed this herself when she said she “would” live in Ponyville if she had a friend. Apparently The Mane Seven didn’t apply (Of course Pinkie would be the exception, but a person needs friends outside of their family.)
Starlight Glimmer filled that friend role and if My Little Pony has time to explore this friendship a little more, viewers will have a great example on friendships with introverts.
Starlight also provides the most logical way to further expand Twilight Sparkle’s character. Since Season One, Twilight has shown herself to be so capable in both diplomacy and battle that it’s hard to imagine what could still challenge her. If any monster topped Tirek in ferocity, it would just be too over the top. Friendship conflicts with different characters could still provide that challenge, but Twilight has so many friends already that her circle would start to become a bit crowded. Plus an episodic series of friendship problems with one-shot characters would start to get redundant (especially after they’ve already done it in Season Five.)
But a role as a teacher is one of the few things that could both thrill and terrify Twilight. It’s the closest thing this cartoon is likely to show to motherhood with The Mane Six and it’s also the pinnacle of Twilight Sparkle’s achievement. Becoming an Alicorn Princess was one thing, but as a teacher, Twilight Sparkle is now at a place in which she can measure herself to the standards of the closest thing My Little Pony has to a god: Princess Celestia. As Celestia’s moth faithful student, Twilight holds up Celestia as the most shining example of pony virtue, wisdom and achievement. And not because Celestia was her alicorn princess, but because Celestia was her teacher and mentor.
But Starlight’s biggest contribution is also the most subtle. She gives a canon excuse for the change in MLP’s writing.
There are many new faces in MLP’s writing staff than we’ve seen in the first few seasons. Some of the changes to the writing are no doubt deliberate, but some are unavoidable. With so many new writers, MLP couldn’t possibly produce the same feel as Season One. Nor should it try, or else it would just be dragging on like so many shows that have lived on past their prime. But rather than end the show a few seasons earlier, the MLP writers have masterfully shown evolution in the characters and the show and they’ve been bold enough to make massive changes.
If the show still featured only The Mane Seven and The Cutie Mark Crusaders as the 10 “mane” characters, those differences would be much harder to digest.
But with the addition of Starlight Glimmer, the writers are able to explore the new themes of MLP and their own interpretations of the characters while at the same time preserving the personalities of The Mane Seven. They still change, but these changes come more from character development than from the writers’ needs to share their own artistic visions on My Little Pony: Starlight Glimmer provides the vehicle for the writers to do that.
In Starlight, the writers have all the freedom in the world to develop Starlight in the world of Equestria with The Mane Seven as role models. And if the series (or spinoff) goes on long enough, we’ll get to see the series come full circle a second time as Starlight, like Twilight, figures out who she wants to be and how she measures up with the ponies she admires most.