Don't know who that's supposed to be but it's pretty good.

Hmmm... If with "boxy" are you refering to a "square shaped"?

you shouldn't use the circle tool to make heads, because peoples' heads are not circles nor ellipses

also she seems rather wide and her skirt is very lacking in detail

all those ghibli bases on my thread
and the anime characters
those were all for fun

while "for fun" drawings are generally doodles (which are typically sketches with little color and less attention to detail), this concept doesn't really translate well to sprites

also you won't get better if you don't put in actual effort, even if it is "just for fun"; practice will only make perfect if you're practicing the right things

One thing I've noticed about some of your sprites is that the facial features look out of place. For example, Adeline's face has the mouth and only one eye on the face. If you think about that, how would it truly look from that angle in a real situation? I can almost guarantee you would see both of their eyes. Try using the picture in the spoiler box as a reference to facial features. Usually when you draw the shape of the head, the nose will align with the center vertically if they are looking straight at you. The eyes will also be about halfway down the head. Keep in mind that this is the shape of the head, not the shape of the face.
[ Image ]
Another thing I've noticed about your sprites is that your heads are shaped either extremely boxy, or extremely circular. Unless you are going for a certain style, like having minecraft characters or something, it doesn't usually look that good in the end. Try paying close attention to the shape of the head the next time you are spriting something. If you can get the shape down, it will look much better.
Just instead of showing the Image on a spoiler, why you don't simply post it?
Also, thanks for visiting my little topic *sniff*
EDIT: Ok.... I guess spoiler boxes don't work anymore...?