It looks too bright and saturated, It doesn't looked like a dragon. [I'm sorry if I'm too rude and I am so sorry if its kinda impossible to make it look like a dragon.]

Less saturate it and have some glowing effect like the night sky or the void

Maybe it could look like this?

The colors used for dragon backpack come directly from ender dragon textures, no model changes are planned. Emissive textures would be rather hard to implement for this kind of model.