I figure armor values could really use another /3 nerf.
You could edit the materials.json file. Reducing the resistance values there affects all armor.
Unfortunately not, but it could be easily moved to a world option.
If you count someone adding the lua methods to access monster definitions as part of the mod, then yes it would be. You’d need to iterate over either the armor definitions and decrease their material thicknesses, or iterate over the materials and cut their armor values. Probably adjusting the material values would make more sense, you wouldn’t be able to adjust any armor thicknesses down from 1.
Thing is, material armor values also start at 1…