And explosion sprites.
In today's wars, there are no real battlefields. I think simulating pre-First World War era would show more realistic battles. It might even be easier to mod current nations to something like that. Steam Punk Ulm could be slightly redone, Abysia with lots of explosives and hero with Flame Eruption -style Flamethrower, Marignon with Musketeers, Vanheim with pistol-equipped cavalry closing to enemy with swords...
Maybe we can add new eras in DomIII?