Nice clean paint job. I reckon a bit of ink would liven up your metallics a bit. I like to use different layers of black and brown inks or even greens, blues etc mixed in to ad some depth.
Hehehe... Ok.
The reason i use orc heads in a orc standart is that Patxi was a wandering warrior that traveled arround the old world, fighting against lots of orc and goblins tribes. (And puting their skulls on his standart)
Patxi uses orc skulls to intimidate his troops. His boyz know that if they did something wrong, their heads will be hunging of the "Skull standart"
It´s only fluff ... :P