I thought the quality was borderline personally, I could see it either getting accepted or sent back. There are certainly things that could be improved. Generally your contrast is too low (especially the pants), and you wants wider range of list and darks in your palette. The dithering isn't helping the piece, and isn't really necessary. The palette is a bit boring because it lacks hue shifting, which can be a particular issues for yellows (as in the shirt). So when you create a shade or highlight for a color, try changing the hue, and not just the luminescence. The arms look a little uneven, the one closer to us seems to be higher on the body and less relaxed, as if in a shrug.