Hey entivore, I remember these.
There was always something that bothered me about your sprites' faces. They just seem... indistinct, particularly in the facing down frames. The side views are much better, I think. Part of it may be how the chin does not meet at the same line for each view. The down views seem too look like they're looking up at us, the viewer, and not straight ahead, where they're going. Try lowering the chin line and the eye line. This problem is most obvious in the rotation animation, where the eyes go up as the girl faces downward, when if anything they should go down (but probably keeping them at the same level would work best... though it wouldn't hurt to experiment).