Whenever I fill my armour slots, I feel that the breastplates are always superior to the shields or headplates. I would like to ask if there are any kind of reasons to include shields over breastplates?
Shields usually have effect like "Reveal this shield to reduce little amount combat damage. You may play other armours in this check. You cannot play 2-handed weapons in this check".
However, breastplates usually have effect like "Reveal this breastplate to reduce little amount combat damage. Or bury this to reduce ALL TYPE of damage to ZERO".
Let's compare that your hand has shield+breastplate versus breastplate+breastplate. Also imagine you are facing monster who have sequential combat check 100 and then combat check 100 to defeat (and you are going to totally fail both checks). Now if you have shield+breastplate, you are going to lose both armours and the rest of your hand. But if you have breastplate+breastplate, you are only burying those two armours but at least you keep the rest of yourr hand.
Therefore, having shields (or headplates) don't improve your defense more than having breastplates, because shields only reduces certain type of damage and only small amount. Being able to play other armour seems irrelevant as in the example above. Also, they limit your offensive capability because you cannot use 2-handed with them. (2-handed usually give you better dices than 1-handed weapons)