I'll be honest: It's certainly not mediocre, but it's average at best.
The colors are done nicely enough, (Save for Senketsu's little eye there) and I think you did a nice job on the hair and breasts.
However, the shading needs improvement and the lack of detail is a little jarring. I think it would look better with an outline, or better definition in general.
The skin is neatly done and you did an excellent job on the head, but the armory bits are poorly done. The gradient shading doesn't work well with the armor (Original style or no), and as I said before, the lack of defined shapes is odd too look at, and out of place with the head and breasts so well defined.
You've got potential and talent, I recommend not wasting it. Good job, but you still could do with improvement.