Hey guys,
im new here, however I think I can shed some light on this topic.
Most rank in SW seems to be based off the US Military. So looking at the Stormtrooper Corps and its command structure, I would say they are very similar to the US Marines.
Orange pauldron- low to mid range officers. Platoon leader, company Commander, Battalion Commander, Regiment Commander. Eg: LT, CAPT, MAJ and LTCOL.
Grey pauldron-Platoon Sergeants (Sergeant Majors)
White pauldron-Squad leaders (Sergeants.)
Black pauldron-Assistant Squad Leaders (Corporals). However, Sandtroopers wore these also.
Nil pauldron-Troopers