My backgrounds always appear to be "rough", I'm afraid. I use them to provide colour, but I can't smooth them out because that will make the colour too dark and will overwhelm the figure D: I have yet to perfect the method!
Anyways, I'm quite thankful for your comment and I'm glad you like it!
I -love- the face and mask! The whole figure looks great, and I really like the pose you've used. The eyes are a bit weird (ie one being so much darker than the other) but it still looks good. The texture of the background looks a little messy, and could really do with a bit of smoothing out, but overall the picture looks really good. Great job!