Hi, I have just seen that notification on Discord. (Those are a mess...)
Perhaps we need to consider WHAT resources are more a representation of a 'large amount of access but everyone has it' vs WHAT resources represent 'if you don't have it, you really DON'T have it'.
Yeah, you've nailed it !
You might be interested in the story of Indian "wootz" steel, used in the famous "Damascus blades", which seems to have been the best steel in the world from earlier than ~500 BC to ~1857 AD (when the British shut down the Indian industry and invented the Bessemer process :
https://acoup.blog/2020/11/06/colle...ake-it-addendum-crucible-steel-and-cast-iron/
So a hoplite is a spearman with a bronze weapon, bronze armor and a bronze shield as its' equipment - there is no/limited opportunity to upgrade these properties.
I wouldn't be so sure about that, AFAIK, while the material obviously played a role, hoplites were *mostly* about a very specific kind of formation and training ?
Compare to the very different but way superior Macedonian phalanxes, or to the somewhat superior Roman shield formations (here too, it looks like formation and training had a bigger role than the materials ?)
Should there be a "formation shieldman" (sub)line of units ?
General rule of thumb could be that if a unit requires a raw, non-living(maybe?) map resource - stone, saltpepper, etc - then it can be done without, albeit with the +100% cost per requirement missing or some such. Reasoning behind this is that a "Stone" resource represents a vein of easily accessed, high quality stone for instance, such that the lack thereof merely means lacking a high quality/quantity access of it rather than the somewhat nonsensical complete and utter lack of any stone whatsoever (and the lack of quality/quantity being that which drives up the cost of units requiring it).
Yeah, the resource names kind of give it away : for instance "Stone" is a generic name for lots of different stones (technically obsidian and marble are stones too !), so I guess that there would be an abundance of it in most places ?
(Which makes even weirder the rarity of stone in C2C in the prehistoric era...)
Consider for instance the hand"axe" (not an actual axe, but still a cutting tool) :
Used from ~1,760,000 to ~40,000 years ago :
https://tauromachy.org/2018/07/18/the-handaxe-the-thunderstone-the-ouroboros/
I don't think that you can make those from *any* kind of stone, and the stones good for buildings might not be necessarily good for tools ? (And vice-versa ?)
Maybe it needs to be separated into building-grade and weapons-grade stone ?
I think you mean Saltpeter / saltpetre aka potassium nitrate aka niter / nitre ? And/or I guess also the other nitrate salts ?
I might be wrong, but they don't seem to be very abundant ?
Well, it's like Uranium, technically you *could* extract it from seawater, but not without some science-fictional tech ?
(Also, it looks like saltpeter was occasionally made from animal waste (bat guano, human pee/poop...), for instance by Confederates during the Civil War ?)