The first, second, and fourth are pretty good. The first one being the best. However some of the proportions on them are a bit wonky. I recommend that you reference an anime/manga picture as you draw. No, you don't replicate the entire reference image, it's quite helpful just to get the basic concept off an image and make something entirely different and new. The third image (The side view) of the girl would be ok if it weren't so flat like Tommy said. You also should work on the third images forehead for it is quite too big.