Primitive Materials and Balance

[deuxhero]

Remember that "Masterwork and magical fragile weapons and armor lack these flaws unless otherwise noted in the item description or the special material description." So fragile is less of an issue one you get past the early levels. Though a character might still be constrained by what types of armors and weapons could be manufactured (before stuff like dragonhide come into play).

Note that hardness/HP is still a little less (and for what little it is worth, an obsidian weapon isn't metal) but nobody uses sunder anyways