Some brief thoughts about the Weapon Distinctions for Slashing and Crushing.
In the descriptions of the Weapon Distinctions Slashing and Crushing are modified based on the kind of armor the target is wearing. Slashing does 1 less point of damage to anyone wearing armor.. any armor at all. This means that weapons like the Katana can be effectively mitigated by wearing the cheapest armor, or gear that might qualify as heavy work clothes. Historically this would have taken much of the appeal out of bladed weapons as symbols of the warrior class, as pretty much everyone on the field of battle would have been wearing some kind of armor.
My house rule is that Slashing does 1 additional point of damage against unarmored and Light armors, as Light armors tend to be 'flesh-like' materials like fabrics and leathers subject to being more effectively 'cut', while the more rigid Medium and Heavy armors are less subject to the slicing edge.
Crushing weapons on the flip side get their bonus of ignoring one point of Armor against Medium and Heavy armor, but lose a point of damage against unarmored and Light armors, which makes sense as the flexible materials of Light armors act as padding and return to their original shape after impact, where rigid Medium breastplates and Heavy plate armors suffer from increased deformation after repeated impacts.
(Essentially you work Light armor materials with cutting implements, Heavy and Medium rigid components are shaped with hammers. Facing these kinds of implements in battle means your armor gets "aggressively reshaped" and not to improve the fit.)
Of course not all weapons occupy either Weapon Description. Axes for instance have the heavy impact weight with a cutting surface, so have neither Slashing or Crushing (which combined are worse than none at all). Some swords might not qualify as 'Slashing', and likewise some polearms might not benefit from "Crushing".
I know Chain Mail doesn't really fit either description of flexible or rigid armor materials, but for game balance reasons I'm loath to reduce "Crushing" weapons to getting their bonus only on Heavy armor which is the least common type of armor you would encounter, making Crushing weapons the least popular to carry.
(This rule applies to firearms, and vehicular weapons/armor as well.)