While I agree with the rest of your post, I just want to comment on the bolded part. As far as I know they primarily mana tapped into magical/elemental "creatures", infact even ingame if you go to their starting areas, and target these mana Wyrms (or whatever they're called), you'd see the tag "Elemental" on them, as opposed to beast or whatever else they might be labeled as.
Ofcourse I'm not entirely sure the elementals of Azeroth can or cannot be called living things in the traditional sense of it, I'd have to dig back and re-read the elementals part of chronicles.