I say both because then whats the point of customizing your spartan if the only time your going to see his whole body is when you die and at the lobby. Well thats if even allow you to customize you spartan in halo 4 anyways
How about not so much attachments but different types of a weapons. Like the O.D.S.T's in halo3-O.D.S.T had a type of an SMG that samed more used for stealth than the one you get in halo3.