I wouldn't call it frightening because she looks calm. I'd tend to classify it as ambivalent - youth (symbolic of hope, future etc.) surrounded by destruction. I suppose her demeanor in the photographs could symbolize the attitude of being indestructible that is common in young people.
I like the way 1 & 2 seem to be a continuation of each other, but i guess that's probably cos i am seeing the stacked vertically.
They are all pretty nice but no4 would be my favourate with 8 being my least favorite.
I don't know why some people don't like the model and the environment together, i think they work really well, i guess i maybe like the ambivalent nature that someone else suggested.