With the upcoming changes to weapon enchantments, which from what I can tell was mainly aimed at dual wield and not 1h and shield, I think there is an easy way to give the lost effectiveness back to tanks. Prior to this change I am pretty sure no one was saying tanks were broken so I see this as a welcome way to fix dual wield while not nerfing tanks.
Change to Sword and Board Passive
Current
Rank 1: Increases your Weapon Damage by 3% and the amount of damage you can block by 10%
Rank 2: Increases your Weapon Damage by 5% and the amount of damage you can block by 20%
New
Rank 1: Increases the effectiveness of weapon enchantments by 50% and the amount of damage you can block by 10%
Rank 2: Increases the effectiveness of weapon enchantments by 100% and the amount of damage you can block by 20%
This removes an arguably useless passive and replaces it with a useful one that addresses the nerf brought about by the recent change.