1st is not bad.. control ur exposure abit, it's a bit overblown, but if that's the feel u want. i have no comment.
2nd is oof, underexposed. since the light source is from the back, u can try use fill in flash.
3rd lack in composition, if u can, should show more of rocks on the bottom right. If u cant, dun include the rocks then.
4th the background seems to be annoying.. haha...

Try to shoot some with half body, or full body. ^^ just my 2 cents....