The character looks great. The only issue I see with it is in the manga preview. It's way to smooth looking for manga.
To counter this, look for a halftoning feature in your image editing software. (In Photoshop, it's in filter>sketch>halftone...)
Here's your character with a halftoning effect and some minor contrast adjustment applied to it:
If you have Photoshop, you can make the process an action so you don't have to manually apply the effect each time.