Hey Dan,
One thing that\'s tough to get with NMM is contrast. Try to push those darks just a little bit darker, and bring those highlights out more. It\'s on a difficult surface too, as on that imperial eagle there\'s many different feathers and angles to think about.
Remember that since the surface is really polished, there\'s going to be all sorts of reflections, rather than just the horizon going down the middle. For example, since the top of the wings is rounded (like a horizontal cylinder) there will be a horizon line on it. Since the bottom part of the eye sockets is rounded off and a portion points upwards, there would be a highlight on it.
(If I had the time right now I\'d draw what I mean in Photoshop, but it\'s 5:30 AM here right now!!!) lol
You\'ve definitely got the right idea, and you\'re going in the right direction. I\'d recommend practicing on a smoother, less complex surface first, just to get the hang of it. Try something like a scrap sword or even a cylindrical shape.
Hope this is helpful! Keep up the good work,
-Matt