Plate mail is beyond the capabilities of category 1 smiths. They can craft crude swords and tools, and maybe simple shields or splint mail from metal, but that's about it. You should probably think more light to medium rather than heavy in terms of armor. A heavy armored warrior in your nation could be one that carries a big bronze reinforced shield, skullcap, studded leather harness and maybe splint mail as shinguards/armguards. How does that sound?