I save the best things for double production week, and only make simple things like iron and adamantine steel the rest of the time - but I really regret spending my coal stockpile on iron, because NW uses tons of coal for cooking. so now I'm not forging anything until double production or Terra. but I suppose I could make more ada. steel since it takes no coal 🙂
once double production comes around, my current plan is to make electrum and... orichalcum, I think? I need to make my notes less cryptic 😛 but those have the best xp/hour... maybe I'd do a little amazonium when I don't have time to check every hour, but electrum is a better use of my limited silver.
I wanna redo the calculations at some point, though, because double production doubles the output but not the input, which might change which ones give the best xp gain/hour.