My question about Commerce is this: will Mercenary Army still be useful if you don't get it right away? Commerce is usually a tertiary tree for me, at best. But if I want to get Protectionism some time in the Industrial Era, will Mercenary Army be a complete waste of a policy? Or will I be able to do something else with those Landsknecht?
Even if you can upgrade them into lancers / anti-tanks / helicopters, I probably would never use this policy post-Renaissance. Especially if the upgrade cost is the same as Germany's was. The upgrade cost is related to the difference in hammer cost between the old and the new units, but Landsknecht cost so few hammers that the cost to upgrade them into lancers was even more than it was to upgrade pikemen, hardly any cheaper than buying a brand new lancer, which most players never do anyway. If the upgrade cost is prohibitive and all you get is a crappy lancer / anti-tank / helicopter (not to mention it'd take 3 turns of upgrades to get your helicopter), it seems like this will be a waste of a policy unless you get it as soon as Commerce becomes available. Its only value would be to get to Protectionism.
Even if you can upgrade them into lancers / anti-tanks / helicopters, I probably would never use this policy post-Renaissance. Especially if the upgrade cost is the same as Germany's was. The upgrade cost is related to the difference in hammer cost between the old and the new units, but Landsknecht cost so few hammers that the cost to upgrade them into lancers was even more than it was to upgrade pikemen, hardly any cheaper than buying a brand new lancer, which most players never do anyway. If the upgrade cost is prohibitive and all you get is a crappy lancer / anti-tank / helicopter (not to mention it'd take 3 turns of upgrades to get your helicopter), it seems like this will be a waste of a policy unless you get it as soon as Commerce becomes available. Its only value would be to get to Protectionism.