Ok, I'm working on the same model at the moment & I'm fairly new to painting minis. I have found successful results by looking at as many well done medels as I can and trying (usualy fruitlessly) to emulate. First thing you should do is go back and touch up on where you've accidentally painted colours you didn't intent (example: right foot). Also, the gems might want more attention. You don't seem to fully cover them, so just go and get all of the gem surface. When highlighting, try not to go for all straight and parallel lines. On the inside of the lower leg, curve the line toward the bottom so that it blends smoothly. Ok, because gems are so prolific on these models, I'm going to tell you my baisic method; Paint the gem black, then paint about half of it a deep red, then do a crescent along the bottom in a lighter red, then add a very small dot or line of white opposite the lighter crescent. Experiment with the larger ones first.
IMO you could do with a thinned down brown/chestnut wash on the wraithbone. Also you appear to be highlighting in slightly the wrong places (used to do something similar myself) try highlighting the raised, upwards areas where the light would catch, not just highlighting the very edges of the armoured plates...
Glyn