Personality:

Misty's personality is that of a tomboy, yet she has a sweet heart. Especially when it comes to Togepi. She's unique and isn't such a baby like all the other characters. She's also a lot like me ^_^ Her words alone can do more than her physical torture, which can save a lot of breaths. She's quite a rage, which I find very usefull for a girl.
Yet she's also very caring and she's got a lot of motherly instincts for Togepi, and that's good too. She's into romance like I am, and dates could never be easier, except maybe when it comes to Ash.
Basically, her personality is split so she can be mean and nice at different times. That's really what I like about her, and why she's my favorite character.

Style:

Misty's style is horrible, I admit. She's got to lose those suspenders and get a longer pair of shorts, but she has a nice sporty look to her. She obviously has no time for hair, which is why she always leaves it in the sideways ponytail. Though that means looks aren't exactly what she cares about the most.
Going back to Pokemon Fashion Flash, you'll think she just cares about looks on the outside. She was actually fighting over how both the inside and outside count. This means a bit of sense in herself. Everbody should care about the inside, true, but if you don't care about how you're dressed at all it will give a bad impression on you. For special occations you should look your best. Don't go to a ball room party dressed in ripped up jeans and a sleevless worn out shirt ^^;;
Besides, her first look with her hair in the two buns actually looked nice. It was just that big red blotch of paint on her nose that ruined it the second time.

Anything else?

Yes! One very big reason Misty is my favorite character is because she's one of the characters who are a lot like me. I got my hair dyed red, and looking in the mirror makes me think "Wow... I look like Misty with brown eyes!" But besides looks, I've got a split personality. I'm very caring most of the time, and if I had a Togepi I'd probably act like Misty did. Though I'm also a tomboy by nature. I may not be the most active kind of person, and I'd much rather take a pencil and draw like Tracey does, but I do, actually, act like a guy a lot of times. I yell a lot, and I'm into romance a lot. And I guess I'm brave enough to say I kind of have a thing for younger guys ^.^;;

Aside from any of what I've said, the last, and biggest reason I have Misty as my favorite character is because she's one of the only female characters that are easy to remember. She's not just some simple side character that battles Ash, she's been introduced in the first episode and she's been in every one of the others since. She's an actual character in the series and is second to the main character. She's never left like all the other girls and she'll always be in every episode. That is why I like Misty.