Another idea that I think would be cool would be melee weapons for Khornates that harvest the Blood Tithe (Codex: Khorne Daemonkin) and let the player spend it to boost their own prowess, debuff the enemy, or summon daemons.
The lead game designer has a boner for Deamons (and we were already told his intent is to get Deamon in as Elites first), i wouldnt be so sure in your statement.
I love 40k and this game but somedays I wonder if we will ever see lore friendly cosmetics I mean like for WB have a shoulder pad with skin stretched over it with writing or their lore style of helmets, what I mean is NL have 3 nice lore helmets I my self love the skull one but nuthing like that for the others makes me sad I would gladly pay to own one from the others but those new ones I would ask why we arnt SM we are CSM scary shit on my helmet intice fear shit like that not sone pre heresy helmets.
Global Agenda had a cool system where the medic class could spec as a 'poison medic', the class had more offensive firepower and a lot of DoT abilities but his core role was still to help his team through focused heal. It's a shame that AS are rather combat ineffective. Even TF2 has medics that can use equipment that makes them 2nd best only to the Spy in melee.