Sorry for the slow reply and the hasty edit -- Here's what I meant:
About frame 4-14 I fixed the sash a little to show what I meant regarding the 3d depth of the ribbon/cloth thingy, but your edit wasn't far off except you didn't put enough shadow across the form in some areas (such as the thin line of pixels moving down the sash over a couple of frames as it flops outward via the windy gust). As counter-intuitive as it may seem at first, it's highly more appealing to use shadow movement to crease the form as often as possible where it can make sense because this adds a lot of life to the subject and, as mentioned previously, it creates a lot more change (even if that change is made primarily with color!) In my edit, I have tweaked the lighting on the belt (but ONLY for a few frames -- I left its movement the same more or less silhouette-wise, and the others I left alone entirely -- hasty edit, as mentioned before, but hopefully you get the general idea).
Additionally, if you study the frames I mentioned, you'll notice that it allows the viewer to get a better sense of the form when you can show large surfaces (such as the tops of the waves of the ribbon/sash) and edges across the front of (even very thin ribbon-like) structures. You'd be amazed that, despite the obvious thickness of a single pixel, indicating edges via movement with those (like I did even with the "ahoge" you mentioned) creates a lot of information that the pixels themselves, as a static image only, could just barely hint at.
The biggest issue with the hair that I tried to explain before was actually in the wind direction of the belt and the hair, not the ahoge. The hair looks really cool, but as others mentioned, it appears as if she's standing under a helicopter that's just throwing wind straight down in waves. While that works, more or less, if you have no other way of indicating movement with a sprite's hair for one reason or another, you should consider having the hair mimic the most important frames of the belt if you can. This is particularly useful when the hair mimics the belt where it curls from the wind at the tips. Hair movement is rarely different from soft-cloth movement.
The original hair indicates wind direction is straight down (as mentioned by others as well as myself), so it looks very much at odds with the belt's movement (despite the belt helping to add a LOT of character). The simplest way to fix such strange movement, at least in this character's case, is to remove the spikiness from the back of the character's hair during the wind change direction (the gusts that kick the belt around to the left) to minimize the appearance of the wind blowing to the right (from the front of the character), since the wind appears to be coming from the back of the character during those gusts, in relation to the belt. I just kept the nice flowing shadows, but shaved off the spikes during the gust frames. Doing this allowed a nice transition between wind-directions thanks to the gust, and gave her hair a lot more life because it created a lot more
change in her otherwise repetitive hair cycle.
Keep in mind that anytime you can add in "waves" of secondary movement and vary them between some other portion of that movement (by offsetting them in time or space), your character automatically begins to look more alive and lifelike because that's how nature works -- through cycles of change -- and very few things in nature move lock-step with one another. The more you attempt to mimic this rhythm in your art/animation, the more your stuff will attain a look and feel that appeals on a deeper level to the viewer because of their connection to this rhythm.
I hope this makes sense.
