For the big snowy circular particles, it'd be nice if you could increase the variation of gaussian blurring between particles of different sizes (have the ones closer to her face less blurry and vice versa, stuff like that) to be a bit more like this
As for the more elliptical ones ... hmm. Looking at the picture again, the two really big ones don't seem as out-of-place anymore, though they still look a little plain. I think it's more than just the blurring at this point, and I don't want to get terribly specific about them, so it's up to you :s
Oh I see what you mean now, thanks :D
