Crafting armor out of natural materials is very cool. Adding some small benefits outside simply cosmetic makes it feel a little more worth the time and effort. Also useful specifically for the Druid. You could also consider giving special materials benefits that mitigate small parts of the normal armors. Maybe a medium armor that allows +3 DEX, or a medium armor equivalent that doesn't impose disadvantage on Stealth. Buoyant armor that provides a bonus to swimming checks, armor that provides natural camouflage, the possibilities are endless.