Ah, I love combining one genre with another style

What would Serenity look like if she joined Belle, Aurora, Ariel et al? Probably something like this.
Putting on my Disneyfication hat, I made the odangi a bit more natural-looking (her original tennis-ball odangi would have made her look a bit too much like Minnie Mouse). The construction is a lot rounder and more solid than Takeuchi's extreme stylisation.
I figured Disney would probably not let her keep the empire-line gown and give her a corseted wasp-waist like the other girls.
Serenity's gown is also mostly white and yellow, which might seem a bit too bridal, so I added a touch of mint green.

I deliberately coloured her to be as close to animation-cel as possible. Disney do not do elaborate hard shadows/highlights on their characters like in anime, it's all just one *simple* tonal layer applied with a gaussian blur in compositing. Anime shadowing is more elaborate because the animation is more limited(more held cels where nothing happens), so fewer frames to draw. Disney is a full 12-24 drawings a second, so the simpler the better.