The Heroes Forge does produce orcs. I'm just confirming that.
I cater the Spire completely. I cater my provinces encounters completely. I think, if I were to replace all my military with goods production, I could probably cater the tournament and maintain at least a 4000 point average. I'm in ch 17 and with a minimum of production (3 T1, 1 T3, a large library farm and various other productions buildings), I seldom have a shortage of goods. In fact, never. So if I removed the 5 armories and relied on my 23 Orc nests, then replaced them with some goods production I think that would be enough...especially if I upgraded my Mountain Hall to lvl 30 (or whatever the maximum might be.). So can you cater all the way? I think you can. If so, then the military would be a waste to improve/upgrade after having enough to produce the needed orcs and an occasional quest.
AJ