Why are you limiting armor in the first place? Lack of metal? Alternative materials will handle it. "Realism"? Well ... any armor that realistically adds protection is going to be hot. Chainmail bikinis are mostly a thing of the past because it's obvious it's pointless.
So ... either just accept that you will have no PC that is strength based (except maybe barbarian) or come up with alternative materials. Or, of course, just accept that D&D isn't realistic.
So ... either just accept that you will have no PC that is strength based (except maybe barbarian) or come up with alternative materials. Or, of course, just accept that D&D isn't realistic.