Hehe... I can do only those chibi primitive pictures, "real" Mika I can´t draw
Well, I think it will be better with good crayons, ´cause those you´ve used are really pale and of poor quality. And why you didn´t colour his skin? Try to do shades (I don´t know how say it? Sciagraphy? Hihi ^^), it will make it real.
And don´t worry, outlines are good (maybe mouth is bit strange) Really, try that with colours and draw more often, it will be great!