Comments posted about your Placebo film apply (especially colour), but here we need to look at exposure. I'm guessing your camera is set for auto-exposure which means it has adjusted the iris for the overall amount of light in the picture. This means that the image is underexposed for the subject (you and your sister).
What you really need to do is increase the exposure so that the dancers are exposed correctly, so we can see more detail. This will mean the snow is overexposed, but that doesn't matter: we will still get an idea of the background, but we will be much more focused on the dancers.
An alternative to this would be to decrease the exposure even more, This would make the subject appear almost as a silhouette, which may be an interesting effect for this particular piece.
As it stands it's neither one thing or the other as far as exposure is concerned.
As far as the content goes, I lost iterest after a while, but regained it once you introduced the secod person. This suggests to me it may have benefitted from having les time on the solo performer and more with the two of you.
Incidentally, I suggest you look at some of the stuff posted here by Kartiv2 . No a million miles away from what you're doing here and very good.