It's time for...
ADVICE SESSIONS WITH YOUR YOUNGER SISTER!
OKAY so first thing's first. Looking at your art, you're really talented. But think you could improve on some things. Like...
Your shading. It makes everything look too smooth.
Your clothes look too smooth. As an example, look at how this person drew the clothing:
[link] There are bumps and lines showing the little folds in the clothing. And this one:
[link] This artist (one of my favorite artists on dA) has used the lighting to her favor, and gave the clothing dimension and shape with it, along with using lines to show folds and creases in the clothing and hair.
For a semi realistic drawing...
[link] Pay attention on how she shapes the clothing and hair and face.
And with this one:
[link] the artist used lighting to make the folds in her jacket look real. Like, more light shone on the parts that were pointed outwards and such.
And in the following pictures, I want you to just observe how the person made the lighting and the lines and the olds and creases...
[link][link][link]And I highly recommend looking at this
[link] artist. Don't copy her style or anything, but see how she does everything. And just look at your favorite artists and just see how they interpret all their lines and folds and creases and hair and everything, and then experiment yourself and see what works best for you.