Animation changes have happened throughout the series, so that isn't really a "reboot." Getting new outfits, even if it's Team Rocket's first, is also not really that much of a reboot. A reboot requires an absolute fresh start, and the only way to truly accomplish this, is if ABSOLUTELY NONE of the old things or the old characters return. Meaning, it's an entirely new cast, with absolutely no traces of the old (in other words, Ash is completely absent, and Team Rocket doesn't even exist, among other things). Thus, although close, it is not a truly complete reboot.
Even IF Misty, May, Brock, Tracey, or Dawn have absolutely no appearances or even mentions afterwards, it's still not a complete reboot, due to the simple fact that Ash, Pikachu, and Team Rocket are still present.
At least one Misty fan has reasons for wanting her to return that doesn't even deal much with the girls (PokemonFan132 mentioned that Misty's goal was far from complete. And I agree, especially given how this show treats the Gym Leaders as being no different from Team Rocket, and the latter case has been classified as weak because they lost to a Caterpie who was not only completely inexperienced, but also barely even functioning. Misty's goal was to become the worlds greatest Water Pokemon Master, something that cannot be achieved while at the Gym.).
And honestly, you don't even know why Misty would even come close to being classified as a better role model. Ever since 1999, when I showed Princess vs. Princess to a relative of mine, she saw how Misty was different than the other girls in that episode, those girls who acted like a bunch of animals. In 2002, this same relative even mentioned that the girls in love hina were horrible. Heck, when I saw May in a Disney Adventures magazine promoting AG, I paid no mind to May at first, even when I knew she replaced Misty (although I never knew why or how Misty was replaced). All that changed in 2006, however on May the 25th. I went to Scottish Rites Pediatric Hospital shortly before my Freshman finals were completed because my chest was giving off pains and also experiencing a dry cough. While waiting for my 2 X-rays to come out, they had Pokemon airing. Although I didn't see May, I did hear a whiney, poodlish voice, and I realized then and there, after thinking I heard May spoke, that she was very similar to the very FAS that I and my family hated.
Not to mention that the book The Rise and Fall of Pokemon actually referred to Misty quite a few times, and yet surprisingly did not mention May, or even AG at all, despite the book being published in 2004, which by that point was either nearing the end of Hoenn, or just starting, depending on whether its referring to Japan and America, and quite a few other sources had praise for Misty, many of which were even research papers and not fansites.