I do think defining the wings and making the colors darker would really make the details stand out, as would darkening the shading around the wolf's neck. Also, I feel as if the rocks he's standing on are a bit distorted....it's like he's standing on the edge of a very steep cliff. See, the 'camera' is looking at him head on, but the ground appears as if one was above the scene, perhaps more foreshortening would help? I'm not very good with the linear stuff.
Overall, though, very nice! The wolf looks great, especially the fur!
Okay, but I think making them just a bit darker would just make them stand out a bit more. That's all I meant.
Well, now that I'm looking at it....is he flying? (Sorry, not feeling my best today. ) If so, then I think possibly raising him up above the landscape just to show that he's not standing, but flying, would really help. As always, of course, this is just a suggestion!