If it were up to me, I would have just made Dawn the star of DP without bringing Ash in. DP could have been the start of having a main protagonist other than Ash. Her first episode was completely about her, and she has more of a personality than Ash did in his first episode. If it wasn't for the fact that they showed Ash towards the end of the episode I would have thought that Dawn was the new main character, especially by how she was in the center of the eyecatches and had her own theme song with several versions of it made. Hell, they still play it in the background of some BW episodes. So basically, I did like her role on the show and I could see her being a main character without Ash being involved. Then again, they did pretty much just make her a female version of Ash later on, while even giving her a mascot pokemon that wouldn't evolve.
I liked Dawn in the show, and it's not just because she's cute. I couldn't care less about her team because DP as a whole were more focused on characters and character relationships (except for quite a few of them). She's my favorite out of the entire cast, because her character was more realistic other than the fact that she's just cute. I can understand why some people dislike her because of her voice, since dub voices in general tend to be really annoying. But overall, she is my most favorite character in the series by far.
I loved her role on the show.
I genuinely enjoyed watching her develop as a character throughout DP, from her very first contest to the Grand Festival finale. She had a great chemistry and close bond with Ash which none of the main girls had before (not at the same level, at least, I mean - they sang an OP together dedicated to their high give, lol) Needless to say, I also dig the team she was given, Mamoswine and Togekiss (particularly Togekiss) are some of my favorite Pokémon. Piplup was hilarious. :D
She was okay. I'm very indifferent about her role on the show.
I didn't hate her at all, yet I didn't like her, either.
She had her moments and I did feel sad for her when she lost some of her Super Contests, but she felt too much like Ash at times to really distinguish herself from him sometimes.
All in all, she was cool, but not my favorite female protagonist.