I don't understand where you're getting that the show is making Egwene the best most specialest girl? It's Nynaeve who saves everyone with an extraordinary, unexpected display of channeling, not just once but twice. It's Perrin who has the unique, one-of-a-kind kinship with wolves. It's Mat who can somehow resist an evil, cursed dagger far longer than any normal person would have been able to do. It's Rand who is the Dragon Reborn. For all her potential, the most Egwene was able to do with the One Power all season (until the finale) was light a small fire and unfasten Perrin's bonds in the Whitecloak camp. There's literally a scene where she thinks she's being described as the most powerful channeler in centuries, and then gets the wind taken out of her sails when it turns out they were talking about Nynaeve. Don't get me wrong, I disliked that they gave her a moment of healing that logically should have gone to Nynaeve, but it was nonetheless the first and only really extraordinary thing Egwene did all season, so I'm confused why you think they're making her out to be the best and specialest? In my opinion she's been pretty ordinary compared to the other Emond's Fielders.
It isn't about who caused the most CGI to be used though. It's about how the narrative frames her, how other characters see her, and what changes were made to the books.
(I will be making comparisons with the books but I won't talk about anything not covered by the adaptation.)
She is the first of the Emond's Fielders we meet. Nynaeve is also there, but the scene is Egwene's, it's her special ritual, it's all about her. Then we see Rand, but he is doing something mundane, and only after that we see Mat and Perrin with Rand, but this scene is actually also about Egwene. Introducing them like that doesn't establish an ensemble cast, it establishes Egwene as the main character. (And I know that Rafe wanted more time, but we're looking at what ended up being made, and besides, we know that he planned to make the women's circle ceremony longer.)
They made her a Dragon candidate, which I don't have a problem with per se, but in the books she decided to leave with Moiraine and the others all by herself, just because she wanted to. This establishes her personality and what she wants in life very strongly.
(It is also the source of her conflict with Rand. They both behaved like egoistical children about it, but we still could have had characters in a relationship having a conflict that isn't about their relationship.)
Because of that change, she show gave her Rand's lines about how the trollocs are actually after them and they should believe Moiraine about that. This made Egwene look like she is the only one who has any braincells among the Emond's Fielders and make Rand seem like the most irrational of them. Similar thing happened with making Egwene the most rational and heroic when talking for going to the Eye, while in the books it wasn't even a question (the situation was different but still extremely dangerous).
That story about how Egwene got sick as a child was turned from the story of how Nynaeve channeled for the first time – to save a dying child and not a guy she barely knows! – into the story of how Egwene defeated a deadly infection by sheer force of will, apparently, which is just dumb. Someone should have caught and rewritten it during all that time the production was delayed because of a deadly infection going around.
That sequence in the whitecloaks camp you don't seem to think was very impressive still makes Egwene, with her one channeling lesson, infinitely more competent than at least half a dozen Aes Sedai with all their training and years or decades of experience. I like this scene, Egwene is great in it, and the Aes Sedai really aren't as good at what they are doing as they advertise themselves. But the show hypes up the Aes Sedai so much and this undercuts what it is trying to do.
All this focus on Egwene even changes the themes of the books. In the library when Rand picks up The Travels of Jain Farstrider in the show it reminds him of Egwene, while in the book he thinks about how Tam always wanted to have this book in his library. It would have been nice to have this scene, especially with how little Tam we got. Then, in the last episode when Ishamael tries to make Rand do what he wants he creates an illusion of Egwene and Rand refuses to give in by giving an impassioned speech about how wonderful Egwene is and how much he loves her. In a similar scene in the book Rand sees his adoptive mother, Kari Al'thor. This scene has its own issues but instead of fixing them the show once again replaces familial love with romantic love. And also turns Rand into an extremely flat character who only does what he does because of his girlfriend and not his own moral compass.
Again, I am not against them giving Egwene more focus than she got in the first book. But the show overdoes it, which hurts the characterisation of others, erases some of the themes that are extremely important throughout the whole book series, and even undermines some other things the show decided to emphasize more in comparison with the books.
