Remember, these aren't our standard outfitted elites. They're a splinter faction, with less resources. This is what I'd call a 'Light' version of the combat harness from Halo 3. Though I think the one from Halo 3 looks better, this armor makes more sense for the Storm Covies.
I guess the Idea is to make them more rag tag. It looks like their armor is lower quality, like it's not military grade.
I liked the Halo 3 Default Elite helmet and the Reach wrist armor better