About the part with the damage numbers not translating 1:1 to damaged armor tiles: I would think that some weapons are specialized in dealing structural/internal damage, so this might be intentional.
Again, this was the only weapon that did not match, even though other of its family did.
Specialisation against internals exists in the form of bonuses to inflicting criticals, and ill cover those in the next one. Im redoing the first 2 to make them look a bit neater and filling some blanks in them. I should have those 2 done tonight, maybe the 3rd aswell.