Can someone explain what's STEP you PV's all about?

[Larien]

On a cursory viewing, and without looking at the lyrics, I'd say it's showing the different aspects of herself: an elegant side (in the blue dress), a cute side (in white), a sexy side (in red, with curly hair), and the last side I'm not entirely sure of, but something like dark, mysterious, or...what word should I use? I want to say artsy, but that's not quite right either. Anyway, in the end, I think they all combine to show you the final "real" Ayu. Based on that alone, I guess you could say that she has many sides, and shouldn't be judged by or typecast as just one.
That said, I think there's something in the lyrics about having other secret sides she hasn't shown anyone...actually, that may be in the lyrics to "ourselves"...

EDIT: I'm not fond of this translation, since it doesn't work very well in English, but it's the only one I can find for now: http://ayumi.primenova.com/lyrics/stepyou.htm
In the context of the video, I'd focus on these lines:

The gap between idealism and reality
Is so very cutting
And as we cannot cut them off, they are opening up.

(At least in terms of the idealistic image of Ayu as fulfilling one of the specific roles you see in each different "persona" shown in the PV: which is the "real" Ayu? Which you do want her to be? What are you labeling her as? How is she labeling herself? The "final" Ayu I would take as the "reality." How much that blends into idealism as we look at her, though, is the question (we, as fans, don't see her a person as much as we do an idol, so we inevitably assign traits to her that she may or may not have, and elevate her, in many cases, above most people))

So...that's my ramble. xD I hope it's understandable. I kind of feel like even I don't know what I've been talking about now!