Remember people, this isn't a thread to debate who's the best female companion.
That said, I do miss Misty, and I want her to make more appearances. However, I only miss the Kanto Misty, not the boring Johto one that does nothing aside from holding Togepi. I personally think that Misty had more personality in Kanto.
I have to disagree with you.
Misty didn't get enough focus for a long saga like Johto was that is pretty much obvious,but she was anything but bland being full of personality having several achievements there.She actually received little more screen time in Johto than she did in Orange or Kanto.She entered more competitions,did something big about her goal like entering Whirl Cup,battled more trainers,helped save group couple of times like she get them out of forest in Hoot,Hoot episode or helped to save Pikachu and Togepi from giant TR tank as well some of her pokemon receiving some character development evolving like Poliwhirl for example.
In personality department only notable difference which can be noticed in Misty character during Johto was that her temper was used in smaller measure compared to Kanto days.Reason is because she started to develop as character and mature a bit learning how to become more patient not exploding over every little thing which may have gone on her nerves allowing that other sides of her personality comes on surface more often being overshadowed by temper at times in past.
In Johto we can still see Misty being full of competitive streak,sarcastic comments having tendency to tease Ash about his mistakes,we can still see her love for water types and fears(like fear from Gyarados and bugs),we can still see her caring side which was already showed to be part of her character both in Kanto and Orange with Misty being full of personality.
As we saw later on during chronicles and cameos she has developed in nice blend of older and new Misty becoming more responsible person being filled with selfesteem not being insecure in herself so much like she used to be.As its been showed her main traits are being kept still being quirky,sarcastic,witty,spunky,caring side etc with some new ones being added.She is hotheaded and stubborn as well being capable of exploding when provoked enough,but she is also more grown up and mature as person at this point and time.
I find her development being nice thing,because it gives character more more depth making him overall more realistic and enjoyable to watch when discovering different sides about him.
There was more to Misty character than just being violent going on rampage.
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For topic like i said yes i miss Misty and would prefer having her back as main character again because of having many things unanswered never receiving closure to story like goal to become water pokemon master which was left unexplored for most part providing lot of unused material to follow up on it).,having untapped potential to do more with her pokemon team,to expand more on back story(like what happened with parents,from where fear from bugs originates etc),developing her more as trainer.It would be also interesting to see how she would interact with new characters and work now days as part of group.
But since this probably wont happen some good appearance would be satisfying too.
Plotline which would bring Misty to Unova could be some water tournament to advance her dream and demonstrate skills as water trainer(after all she wants to become best water pokemon trainer fitting her)and to catch some new water pokemon seeing how Unova is isolated from other regions making it hard to obtain its pokemon outside of it.
Having Misty meet Iris would to be honest make much more sense than it would be if she met Dawn.Because of Iris connections with 8th gym and Misty being gym leader this characters aside from sharing some personality traits have things in common being beneficial to have Misty back and help Iris about possible gym issues to overcome(like May did when helping Dawn about confidence issues in Wallace Cup).