If you use Craft (Poison) from CV it adds two more categories of material ratio and a new work/week value.
Combined with normal crafting that would give 3 categories of material cost/market cost and two categories for work/week.
Combining them in a matrix would give 6 ways of dealing with crafting as a whole
1/6 material cost, silver pieces per week
For common high demand items with easily accessible/cheap materials and mostly labor costs (basketweaving, woodcarving, etc.)
1/6 material cost, gold pieces per week
For rare specialized items with easily accessible/cheap material and mostly labor costs (simple traps, pits, animal based toxins, herbal toxins, etc.)
1/3 material cost, silver pieces per week
(This is the core crafting mechanic)
The majority of normal items with normal demand and average availability of materials
1/3 material cost, gold pieces per week
For specialized items with average availability but the price is determined mostly by rarity (valuable metal light jewelry without precious stones, low value gem cutting, complex traps, etc.)
3/4 material cost, silver pieces per week
For common high demand items with minimal labor costs compared to the material costs (cooked meats, basic/simple carpentry, etc.)
3/4 material cost, gold pieces per week
For specialized items where most of the value is in materials (elaborate traps, large heavy jewelry, larger gems, exotic poisons, etc.)
You could then break out each specific craft into a material ratio (1/6, 1/3, 3/4) and cost multiplier (normal=silver, x10=gold).
While normal weapons and armor would be (1/3, normal) if they were made of a material that increases the value by x10 or more than I would go (3/4, x10) for crafting (mithril or adamantine)
CV splits poison into (1/6,x10) and (3/4,x10).
Trapmaking could be (1/6,x10) or (1/3, x10), or (3/4, x10) depending on what materials were needed.
Jewelry might split between (1/3, x10) for low value items and (3/4, x10) for high value items.