First off it looks great! Scales are tough to do but you did manage to bring out the larger ones. The lightning and background fits him really well and his expression suits the mood of the image. However something that bothers me are his front legs. From the elbow down they seem a little thin and long in comparison to his reference. Also the spikes/scale things that down that part of the arm get smaller the farther down the go and are also a darker shade of orange.

Something else you might want to change just to bring it out more its not really necisary, would be to brighten his glowing eyes. They seem a little dark to be glowing.

I hope this was a help