Discussion about the Stronghold faction.

How else should they differ graphically?

Take, for example, the alternate and alternate-upgraded Orcs (level 3 unit) in Heroes of Might and Magic V. There is a difference. Or the Chieftains, Tormentors, and Warlords from the same game. There is a difference. Or the Goblins from there. There is a difference. They didn't just add some trinkets; they added different weapons, a different appearance, and a different model in the end.