paulewaug said:
that seems like a pretty good formula
Ironically, this discussion motivated me to go back and finally update the rest of our exotic-material system to 3.5E, which for various reasons required me to redo it all in pounds instead of kilograms. It also required reworking the Craft skill (previously, we just fudged everything under the "it'll be done when you get back from your adventure" system), masterwork rules, some parts of the Monster Manual, and a few other miscellaneous things.
Anyway, I think this change was necessary. Under most circumstances in 3E, weight is a very minor consideration. Someone isn't going to compare the Greatsword to a Dagger and say "you know, I WOULD use the sword, but it's just too heavy." If it's too heavy to haul around, you get a Glove of Storing, or a Bag of Holding, or an HHH. Also, even with a 10 STR you can still haul a big weapon around just fine.
But then, you add a bunch of rules that make the big sword cost 7500 gp (versus 500 gp for the dagger), and the balance shifts. I'm not saying that a dagger should take as much material as a greatsword, but 7000 gp isn't exactly pocket change, even at higher levels. If things like Silver and Cold Iron are priced by the pound, everyone can pick up a 1 lb dagger for dirt cheap, and that's bad for the new DR system.
Even if you're comparing similar weapons (greataxe vs. greatsword or swords vs. polearms), you get balance issues, plus the math headache of exactly how to reduce the weight of a polearm (do I use mithral, or darkwood?). But, if the amount of material needed ONLY depends on the effectiveness of the weapon or armor, this isn't really a problem any more.
One of these days I'll get around to posting the latest version of these rules, but there isn't always much demand for yet another house rule system.