I never tried the mace, but i imagine a mace is a two hand weapon vs the sword that require only one hand wich allow you to carry a shield to block the enemys attack.
The block with a shield often result in the enemy stopping their attack for a short period of time wich allow you to counter attack. Its quite nice.
I dare to say the sword and shield is a really nice combination.
I guess it depend on your playstyle

The strength of the maze is that it have a better armour penetration than the sword and hit a bit harder.. BUT its downsize i imagine ( guess ) is that you cant carry a shields protection and features.