[Agema]

Mm, some nations tend to have large armies of relatively weak and short-lived units, whereas others smaller armies of longer lived units. The former could be quite badly hurt by this unless it is selectively applied because of long-term income damage. It might also make death scales very risky for them, and make growth scales more important.

Furthermore, with reduced gold cost, even if population is reduced (and thus income damaged long term) potentially those nations could become rush nations because they can get hold of so many troops so quickly. Quantity can overcome just as quality can. I'd agree with Gandalf Parker that it would be best implemented on some nations as a balance for the player to consider.

That said, I doubt I've ever had more than 1000 recruited units alive during any one turn in any game I've ever played (although I've not played a chaff-high nation that has survived to endgame like maenad-spawning Pangaea), and probably no more than 5000 in the course of my nation's lifespan. When you consider a capital has a start population of about 30,000, I don't know that troop recruitment will affect that much anyway.