She means your "strands"(the black lines in your hair
). When using the stranding technique, the next step for it is to shade the strands as well, just like you do with the hair(not the same colors obviously, but I mean going down in each palette shade as you go along).
Your shoes could be improved by having a more rounded top to it. They sort of go in at a "V" shape right now and should look more like a half circle. Put on some shoes and go take a look in the mirror. What do you see? Most shoes look like a sideways "C" along the top
As for your pickiness with the pants, I think you are stuck on how your folds were all shaded in your second palette color. You'd see improvement if you had instead a line along the bottom edge of the fold(or upper), then shaded around it with your third and even fourth palette colors, depending on the doll size.
You are showing major improvement in your dolls! I see you have taken on the bulkier shading technique. Not my cup of tea, but you definitely are taking control of it steadily. Try adding more highlights along the tops of the folds, it'll bring the blockiness together more.