Hmm... interesting ideas.
First: I didn't add rust and dust because loyal servants of the emperor are meant to keep their gear in good working order. But I know it would add a lot of interest.
Second: I didn't add displays and stuff because they're not amazingly high-tech weapons. But I suppose it's sensible... I could put it on the little bit just above the shoulder mount. Ammo counter or something, it would be cool if I could animate it like on the Assault rifle in Halo.

Thanks for the feedback!