I'll give this a shot, then.
The first thing I noticed was that her head looks a little lopsided. The main reason for that is that the curve of her bangs don't follow the curve of her eyes. Her eyes, and therefore, her head, have more of a tilt towards our left, but the bangs look like they belong on someone who isn't tilting their head. If you want to draw slanted bangs on purpose, you'd need to make them more extreme so that it looks obvious, otherwise it looks like a mistake. If you meant for the bangs to look striaght-cut, which is what I think you were going for, then you need to have them follow the tilt of the eyes and head.
The next thing I noticed is that your light source is really unclear. It's one of the mistakes I'd make when I was starting out. When putting in shadows and highlights, the most important thing to know is why the shadows and highlights are there. Try to avoid putting shadows all around the edges of things. The sun and moon, and even other light sources, tend to be above our heads and to the right, so pick a side of the picture that's going to be light, and a side of the picture that's going to be dark. Putting shadows all around will flatten out your image. The same goes for highlights. Highlights are meant to make things pop, but if you use them too much, the image will look off. I noticed there's shading on your eyes right underneath the lashes. I'd advise against this because that part of the eye should have shadow on it from the eyelid and lashes themselves.
While I'm on the subject of the eyes, I think it would be better to not have black lashes, or black in the shading of the eyes themselves, unless you're going for a dark image. While you do want eyes on characters to stand out, you also don't want them to be so distracting that the eye is drawn only to them. I'm assuming the base is what had them that way, but I recommend changing the color to either dark purple to match her hair, or dark blue to match her eyes.
In terms of hair detail....If you're going for something as stylized as that base, I wouldn't go for that much detail on hair. You also need to keep the way the hair actually works in mind. Right now the hair has detail, but the hair on her ponytails is going in the wrong direction. If she has curly hair, the hair should follow the shape of her curls.
[Image: http://www.drawinghowtodraw.com/drawing-lessons/drawing-faces-lessons/HowtoDrawCurlyHair_files/image006.jpg]
Random image from google, but it gets the point across.
Next her food: It has only highlights, and no shadows. If you're going to give something shadows, make sure everything has shadows. Otherwise the object without shadows will stand out, and not in a good way.
For clothes, be careful. There are almost
no clothes that will outline the breasts like that, especially not sweaters. Even when breasts are showing the cleavage won't be that dark. I would just take the outline of the cleavage out altogether. My advice for shading clothes would be to avoid anime, manga, video games, and comic book references,and look at real clothes. Those mediums in particular tend to draw impossible clothes, including clothes that outline things clothes don't actually outline, just because they think it's "hot".