More population for orcs,we are supposed to become horde and swarm the enemy.
More mercenaries units:vampires,werewolfs,trolls something to spice things up.
New elite units like dragons and limit them for 1 per army and use rock,paper,scissor implementation(ie cyclops>dragons>hydra>cyclops ,you get the idea,there is plenty of mythos to go around).
It would be cool if in the future we could set our own walls,will lead to some interesting castles.
We need wars between alliances,once you belong in a alliance that has war you can get atacked(and sacked) by enemy,you could request from allies reinforcements(we need some pvp drama:P )
"This is no rabble of mindless Orcs; these are Uruk-hai. Their armor is thick, and their shields broad."