I love this design! Just one thing bugs me: wouldn't it need another arm to draw the bowstring with?
Also, is that 5 appendages I see? Like, the arm to the left holding the bow (right in our view)? I don't see symmetry on the right side. ._.;
There is an eternal sort of problem with drawing this design, which is that I really like how the body looks from the side, and having the other arm out necessitates that I obscure parts of it. It does have the two arms, but they are, by design, normally hidden under the faux-wing covers. You can see the second arm's shoulder just above and behind the primary forelimb's shoulderplate, it has a small armor plate with a dark dot in the middle (an external camera) on it.
I might draw a version of this with the second arm out, or maybe the faux wings open slightly to show where it is.
(edit: ninja!)
edit2: There's
this picture of an Artee, the... less military version of the same design, in about the only circumstance when drawing both arms out seems natural. Yes, Artee does sleep sometimes. The military Artax, not so much.
edit3:
I'd like to see a sketch of how he would use the bow. It seems like it would be awkward with the shoulders further back.
The arms are relatively long, there is a considerable amount of travel in the shoulders, and the bow is a compound one, meaning you only need full strength to draw it first, and then you can aim easily. It does suffer severely from the "horseback archery" problem, where it can only aim in the half-arc of the arm that holds the bow, but thankfully both Artax and the bow are ambidextrous, and standing sideways to the target is not typically a problem.