It depends what you use it for.
Daggers are better because:
You can't backstab with a mace.
You can't throw a mace.
Dagger attacks are quicker.
Maces are better because:
Mace does more damage per successful hit.
Mace damages Clay Golems.
Mace does more damage to skeletal dead.
Dagger cannot be used by Clerics.
It's all dependent on the character class, situation, and weapons available.
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Time is an illusion. Lunchtime doubly so.
Epona of The Laughing Hyenas