"Can you think of a better category for couscous?"
It's own I would guess. Maybe together with Bulgur. Food made from wheat and similar to couscous went out of fashion after northern Europe discovered the potato however, so I suppose there once was more in that category.
But looking a bit further into it Wikipedia also tells me pasta and couscous are similar. Oh well, carry on then ;)
Oh, and that really was just curiosity, because they certainly are not in the same category here.