Tying back to what I said in regards to my post whether Raya and the Last Dragon can fix Disney's current villain problem I also wonder if Namaari will join the ranks of Zuko and Catra, that being the villain or antagonist who turns hero.
She has a lot in common with both characters, like Catra and Zuko Namaari was raised by an overall antagonistic force (the people of Talon have been shown to be rather arrogant or at least the royal family is), like Catra she has a history with the main protagonist which helps to give them a potentially deeper besides just adversaries in a war. Like Zuko her quest is seemingly put upon her by a parent whom she seeks to appease and like both Catra and Zuko she betrays the protagonist's trust in order to achieve her goal.
As Catra and Zuko have proven this sort of character can be AMAZING!!! Both Catra and Zuko are among the most popular characters in their respective series and the reason for that is very simple, their relatable yet still villainous. Catra betrayed Adora's trust and either tried to kill her or left her to die on several occasions and Zuko helped Azula kill Aang and also helped bring the Earth Kingdom to its knees.
Namaari, from what I've gathered, betrayed Raya's trust when they were kids which led to Raya losing her father and starting a 6 year long quest of trying to find the Last Dragon and restore peace to the land.
This would make Namaari a rather unique character as I don't know many villains turned heroes in the Disney Canon. Hell the only characters who started off as villains but turned heroes are Aladdin's Iago and Cinderella's stepsister Anastasia. However, both are the result of the sequel coming in to make them heroes and neither is really that popular, at least in comparison to the villains and heroes.
There's also the fact that neither one of them were really as close to the heroes as Namaari seems to be with Raya. I mean, Raya has kept the necklace Namaari gave her when they were kids even after she betrayed her and even when they're getting ready to fight each other in the Talon village they smile at each other as if this was just a game to them. Putting aside the shipping fuel this gives the two of them (seriously there's already fan art and fan fics of Raya and Namaari) this could help the viewers relate more to Namaari in the same way we did with Catra and Zuko.
The world of Raya and the Last Dragon, aka Kumandra, has some real potential and if the film is as good as I'm hoping it to be I would LOVE to see more of Namaari's story along with Raya and Sisu's. I want to love this story, I want to ship Raya and Namaari (and maybe Raya, Namaari and Sisu as a OTTP (I truly am a sucker for romance ¯\_(ツ)_/¯)) and I want to see if the story is worth all the hype it's giving me. Hell, there are rumors that if this film does well Kumandra might end up being made into a land in Disney's Animal Kingdom on the Asian side of the park.
And I think a big part of any success of this film will be down to how well received Namaari ends up being. Avatar and She-Ra are both great but I don't think either of them would been as popular without Catra and Zuko.