I am practicing the mesh tool in illustrator, I wish to improve my art as well.
This one is a test I made, I sketched the drawing and then vectored it.

Spoiler: show

Hope for good CnC.

ok, so quick one:
im gonna critique the drawing aspect because i dont know much about vectorizing...
1st of all, i think the design is kinda neat but can be better, if you use the hair as a graphical element instead of just "something that is there"
then try and give the whole character a bit of a change in direction, straight on views are kinda unsettling, but that can be just on my side xD
and in general, try to focus on planes and 3 dimensionality.
one last thing, the breasts seem to be growing out of her forearms, remember that they're attached to the chest and are squishy

Okay, I'm going to be sort of annoying, I hope you were looking for real hard truths,Flavian style, cause that's what is going on here.
But, I'll try to be gentle, in this way,
Get more mileage under your belt.
The proportions of the face are very off,and, though her head is facing us, her face is not, it's looking down. There isn't the much understanding in terms of form, perspective, or anatomy here.

Get more understanding of all of these things first, I understand that it is stylized, simplified, but that doesn't mean her eyes should make up 80% of her skull, especially when everything else is trying to look fairly in proportion.

Draw a lot. Don't worry about making master pieces, work on the fundamentals, but most importantly, have fun doing it.
Don't listen to people like me telling you to rip all the fun out of art. I like the way you painted it, given more experience I thing you'd have something really going here.

I would be unhappy with the reply I sent, so let me add this.

It's a pretty piece, if it were in proper perspective with proper anatomy, it would be gorgeous.
Keep it up, I legitimately want to see more from you, I'm only bashing on you because I want you to improve.
.
Packy... out.?

I have edited this for some hours, will take the advice on the breasts.
Hope to see some critiques.

There are still the same flaws from the first post. I am not saying it is bad. It is a good effort for what the mesh tool can do but it seems like the tool is getting in the way of things.

I did a quick paint over to show a closer representation of how the breast would actually behave.


It is like what z4m97 said, the breasts squish. The breasts in you image would be accurate if you were trying to portray big, long, and "tubular" breasts. That is the only way you would have the overlapping you did. In my paint over I made the arms overlap the breasts. This closer to how things are in reality. The reason I think the tool is getting in the way of things is that since you are working in shapes, you are concentrating on one thing at a time and maybe neglecting the piece as a whole a little bit. Think more about how things fit in the entire piece and how one element would effect another. For example one element would cast a shadow on another, like the arms and breasts.