Previously the mortals did have access to magic, but at some terrible cost (which was never explained in lore). If things were very bad, they could become lightbringers, which were immune to darkness, and had cities which remained warm regardless of climate change. That was Shadows 1, it's not yet in Shadows 2 because late-game balance requires the start of the game to be established first, to figure out the different ways the player can reach the late game. Hopefully we can now start looking at that part of the game.
Could be looking at the possibility of giving the NPCs a way to defeat the player, as well as maybe a turn limit. Will need to look into it, especially using automated testing to get a good idea of the statistical distributions we'll be looking at for the end game.
We tried industrial stuff, with long term vs short term economic decisions, but couldn't get the balance to work very well, I'm afraid. It wasn't considered a priority, so we never released it into a main build. Possibly one day, but for now there are other more important things to deal with.