Ragdoll physics would be amazing to see blasts from catapults, knockbacks, etc. I suppose making each unit have a fall animation would be a bit much. I was just thinking more along the lines of every one in ten units that die on a wall will fall to either side of the wall (straight line down) to have bodies litter the ground around the wall.
I think the argument against Ragdoll physics was the whole issue of necessity vs. lagg. It didn't fulfil the criterium of being unquestionably necessary, and would bump up the spec requirements (AFAIK).