I was thinking about adding same new materials. However, I want to mostly try to add materials of lower and middle tier, because we already have some good end-game materials and adding more might lead to CLIVAN-like power creep, where you just find way too much high-tier items. Even adding materials with only some minor variations will look nice for finding different equipment, though, so having eg. several iron-tier materials is still worth it for the novelty of finding "iron short sword" once, and "deep bronze short sword" the other time.
Proposed material with their stats can be found in
this sheet.
I'll be very glad for any thoughts and comments.