A simple mod grants the option to change all three metal plates recipe requirements (Iron, Copper and Steel Plates), either decreasing or increasing the required iron plates / ores, as well as the output amount, limits are set to prevent being too overpowered
Small changes concerning balance, gameplay, or graphics.
All the recipes are on vanilla stats by default, so you will need to change them yourself once you install the mod.
For new or confused players, look in Settings > Mod Settings > Startup
Unlimited version here: https://mods.factorio.com/mod/Adjustable_Plates_Unlimited