The values that the game uses is 5 x [MATERIAL_VALUE:??]
Oh! I had no idea! That's EXACTLY what we want, because metal bars are worth 5 times their material value. So we want to divide all my previous suggested values by five, giving us the follow values which are based purely upon the utility of using leather to construct armor:
Tough Leather = 4 (twice that of copper)
Studded / Scaleplate / Shellplate / Chitinplate = 8 (twice that of bronze)
Lamellar = 16 (twice that of iron)
Rigid Scale = 18 (twice that of iron, + bonus for fireproof)
Rigid Chitin = 20 (twice that of iron, + bonus for being so light)
Rigid Shellplate = 32 (twice the average of iron + steel)
Dragon Scale / Nether Lether = 72 (twice that of steel, + 50% for being light and cool)
For those just joining the discussion, the "twice the value of [base material]" is based upon leather armour items only taking a single piece to craft, whereas metal takes 1-3 bars per piece. Consequently, it takes about twice as many bars to craft a full set of armour than the equivalent pieces from leather.
I think it is not appropriate to be able to produce such high valued armor before the first caravan arrives.
I agree, although I don't think the solution is to nerf the leather values too much, since with artificially cheap leather we can bring tons of it on embark and have everyone clad in rigid shellplate, jumping straight to iron+ levels of protection. I know that in my forts I already buy all the leather every caravan brings, because it's cheap to buy and a pain to produce. However now with the suggested values I've got above, a suit of leather armour would be worth about the same from the equivalent suit made from an equivalent metal, rather than the inflated prices in my original suggestion.
I think the solution to players potentially cranking out lots of high-value leather items is to either nerf the properties of leather itself (to justify making it less valuable), make the exotic leathers harder to obtain (eg: only available through butchering non-domestic animals), or make the higher level reactions more expensive to run (possibly requiring souls, or other rare ingredients).
One possible starting point would be to only have it possible to improve each leather only once, giving us:
* Suede (tier 0, clothing strength)
* Leather (tier 1, vanilla strength)
* Shellplate / Chitinplate / Scaleplate / Leatherplate (tier 2, copper strength)
* Enchanted (Shell/Scale/Chitin/nether)plate (tier 3, iron/bronze strength)
* Dragonscale, Runic netherplate (tier 4, steel strength, fireproof)
* Imbued Dragonscale (tier 5, adamantium strength, fireproof)
This means that rare leathers (which I propose would be from non-domestic animals only) are exciting, because they can be enchanted up to iron/bronze level armour, whereas regular (domestic) leather is not suitable for enchanting. This system also gives us standard names (I've always found the existing names much too confusing). Anything which is "-plate" is tier 2, anything "enchanted" is tier 3, and 'runic' is tier 4. Under this system freshly produced nether leather starts at "enchanted" (and presumably has an appropriately thematic reaction to justify that).
Moving from "leather" to "leatherplate" requires oil and studs. Going fom "-plate" to "enchanted -plate" requires a soul from one of the Great Races. Going from 'enchanted' to 'runic' requires something even more rare, and 'imbued dragonscale' would require at least a megabeast soul to create.
Under this system, copper equivalents are pretty easy to create or come by, iron/bronze can be produced once a fort is involved in active warfare, and steel and beyond requires extensive planning and great victories.
I'm also in favour of combining shell/scale/chitin into a single 'exotic leather' type, which would simplify stockpile management, gameplay, documentation, and OCD tendencies.
2 Studded + 1 Thread = 2 Lamellar (MatVal 11) <- I always thought that you only got 1 Lamellar out of it, but the reaction says otherwise.
This sounds like a bug rather than a feature.
Another thing to consider would be to change the type of armors that can be made from them to max out the armor value at 2 and possibly change the other armor factors. This would make the armors good to start out with, but not a replacement for the true iron or steel armors. (I've never made anything from the Chitin/Shell/Scale varieties and always made the Rigids instead).
It would be lovely see some !SCIENCE! on what difference the armour value actually makes, the current wiki suggests that it's no longer used by the game (which uses material properties like sheer strength), and instead is a placeholder to represent leather (1), chain (2), or shaped/plate (3).
I don't mind leathers being as strong as iron or steel, but
only if such leather is at least as hard to obtain as iron or steel.
~ T