I think RJ's writing of her as a innkeeper's daughter early-on was what I always expected of her throughout the series. I always wanted some element of that person to persist regardless of how her responsibilities changed. The change from Egwene in the first half to the second half of the story is too dramatic to be believable.
I believe this was intentional on RJ's part as he wanted to change the character to more broadly reflect her changed role in the story. But, I just don't see that being a realistic portrayal of a human being. I think she could've maintained the relatively even-keeled, thoughtful innkeeper's daughter from the Two Rivers while having an important relationship with a more experienced advisor like Siuan. This way it could've transitioned her from being an inexperienced, simpleton (but kind), to a kind, intelligent, rational leader surrounded by strong advisers with trusted experience.
Instead, it felt like she was transitioned to an isolated, untrusting, cold-hearted leader that left the reader (me at least) longing for the interesting, emotionally complex character from earlier in the series.