It is a very large difference between your characters when theyre textured and when they're not Did you study 3d your modells seems rather rough even if they are supposed to be low-poly, can you show the wires it would make it easier for us to help you. And perhaps put this topic in W.I.P or finished projects.

Your texture of the agent is kinda nice, some areas seem to have a lower resolution tho, if that is what you're aiming at then its okey, otherwise i think that you should consider making the hair as a model or with the Maya hair system. And what is that white spot on the man's neck? you were to lazy to texture everywhere and you still had a view from the back?

Well otherwise keep it up man!

Edit: The childs hair should look more "loose" right now it looks more like stiff wood or something (try following your scetch closer.)