The warrior default design for Gilden has the Chainmail proficiency, There is no reason for this since Gilden (default Gilden) has no chainmail or access to chainmail armor. Might I recommend a removal of that skill from the warrior design. Maybe add another skill. It seems to be a holdover when mauls and hammers were two handed.
Also, whenever a player selects the chainmail proficiency it should be removed if the faction has the light-plate skill, similar to the plate skill.
Adding this tag to the ArmorProficiency1, removes the option from the list, since the player shouldn't choose this if they are playing with light plate.
Furthermore, let us not forget the NoArmor ability, where the player shouldn't be able to select either of these abilities when that faction trait is selected.