At the moment, maces are equal to hammers in every aspect save their slightly cheaper crafting recipe. I have decided to add a bit of distinction between the two weapons, and add some new maces to factions I think should have them. Now, I think maces should be a little faster to swing than warhammers (perhaps the same as a battleaxe, or a little slower), deal a little less damage, but have the same (or perhaps a slightly smaller) knockback bonus. My reason for this distinction is not only for uniqueness, but because currently the Half-Trolls have both a mace and a hammer, which are identical in combat stats. A distinction gives the Half-Troll mace a reason to exist. Below are a few maces for certain factions. The list is by no means complete. As a side note, all maces use the current mace crafting recipe.
The Black Uruk Mace. This is wielded by the elite Black Uruks of Mordor.
The Gundabad Uruk Mace. Gundabad Uruks use this weapon, and it may spawn in the hands of some Gundabad Orcs.
A retextured Half-Troll Mace.
The Mordor Orc Mace. Used by the Orcs of Mordor, and sometimes by the Orcs of Gundabad.
The Lamedon Mace. Used by the Men of Lamedon. Something to make them a little unique.
In addition, the Dol Guldur Hammer should be renamed to mace.
Hope you like it! Feedback appreciated, and if you think any other factions need maces, let me know and I'll add them to the suggestion.