Some things are also how they are because of the meta. Like scales are better blunt but nobody cares about blunt, its swords and bows online. But some things are just way off. Like messing, is horrific, heavier, worse carapace. And some things need to be more specialised. Arthropod carapace is just better heavier IB. But it could be IB with better blunt and slash but worse pierce. Something different. Like scales. They have a niche. Horned scales vs IB, horned are lighter and better blunt but worse slash and pierce. Theres no reason to have this many materials when some just suck vs others.
Another thing is effort to get them. Heavy carapace is harder to get than Pansar carapace. But is worse.
Weapon balance also needs some love but thats a whole other topic. Theres so much stuff and so few actually get used.