This sounds like a good idea particularly for PvP to create stronger buildings but it would also be good for PvE for making a beefier looking wooden wall. I also like the idea of iron rimmed windows, iron for floors and visible iron floor supports for upper floors to give a different look to ceilings. Then to top it off an iron enforced door maybe with a + look of iron bars and then on the borders of the door. I think this would make wooden buildings look nicer.