You deffinatly know what your doing, but I would recomend a few things: Bit clearer highlights on the machine, I can see you got clearer highlights on the Eldar. Also, don't use Decals... I know it's hard to do freehand, but you never learn unless you try. One thing you can do, wich was the way I started out, was to put on decals, then paint over them. That way you train your eye to do freehand.
Good job, above average.