I found a Pop Growth formula on the Wiki:
Min(BioFactor*Trunc(Round((MaxPop-CurrentPop),0)/3,0),BioFactor*Max(40,Round(0.03*(1-Taxrate)*CurrentPop),0)) (Thankfully, I had figured out the max-40 already but was thinking the hidden modifier is NW or Bushels)
Of course CS is valuable for lowering time to build. I was curious if there's good reason to spend effort building small amounts of structures while making CS :-)
I found the production formulas for Military Units here:
https://wiki.earthempires.com/index.php/Military_Units But I'm having trouble finding anything about Spies. Where can I find a formula for Spy Production?