Well, in the beginning, she acted out of pure innocence, it must have been almost like a game, so she was quite Hermione-ish. In PoA she began losing sight of who Hermione was, she wasn't as bookworm as she was supposed to be, which is what I loved the most about the character. In GoF, she was utterly annoying with her little eyebrows and lame silences before a repproach, and a bit of that continued in OotP. In HBP, she had improved a lot: the crying was impressive, she was truly pouring her eyes out (I read that Dan said she then couldn't stop crying... what must she have been thinking?). I have a lot of hopes for DH, I know she must have honoured Hermione there.
In fashion sense, she was so little and unexperienced and flashed in the beginning that she dressed horribly

Well, not all the time... I liked that she kept being a modest child in interviews, she would only wear a sweatshirt, or a simple top and trainers or boots and that stuff. It was nice, compared to other young celebrities.
In PoA and GoF era, I liked the dresses for the premieres, but for the photoshoots and photocalls it was clear that her sportive self was expressed in the outfits, for she matched skirts with trainers (which I heartly dislike); but at least it was nice to see that she picked most of the outfits herself and she wasn't a fashion waggon. She also used the whole runway outfit when she got stylish.
Her style definitely changed in OotP with Chanel, she started learning how to pick accesories and stuff that matched without taking the whole set from the mannequinn

I love that she still can dress very modestly, simple and unnoticeable even if she's wearing Chanel.
Btw, what a funny picture, arwen!
