Metal Shields
The ability to craft shields with metal instead of just wood. It gives the player more armor but uses up agility. It can have a variety of armor types that gives soft health and hard health just like how equipable armor already does.
Shield Abilities
Reduces the amount of opening you get during combat. One shield could specialize in reducing a few openings such as red and yellow and another could do green and blue. Maybe it could offer abilities such as increased Melee combat or increased strength. Alternatively, shields could also offer openings such as spiked shields (or a shield used for bashing) which would be used with an attack move.
Overall, maybe the metal and special shield types can be fused together. It would be awesome to see more shields in the game although!