@Keyisfull, that's an excellent run down of ways to earn money, there are also lots of businesses you can own or takeover in the exploration screen, like the black market, the magic theatre, the brawl pit, the fight pits, ect that earn you money! 
and now at the start of the game you earn money from goblin slavery, which gives you a reason not to cancel it!
The exploration screen is half finished, I ran out of ideas for the most part and gave myself some space, but there are tons of areas altogether
Races vary massively, from strength, civilisation level, laws, population levels, so some civilisations like goblins has massive population levels which mean they gain tons of troops each turn but usually they are weak, whereas demons tend to have small population levels and recruit barely anyone each turn but are immensely powerful, you can see the independent units battlescores in the in-game wiki if you are confused, or in diplomacy by looking at the troop tree screen, civilisation level at the moment just means if its below three they are too uncivilized to speak to you, which makes them usually more hostile. Laws also matter, some laws mean that when their king dies they sacrifice tons of their own people in rituals, other laws mean they use no currency, other laws mean that they are xenophobic and wont talk to anyone not of their own race, so races do differ alot, also some are good and evil though this means nothing currently! some support demons though and will give the demon horde a boost as well as being unable to be attacked by demons, some kingdoms can be doomed to collapse, which you can find out by looking at the doomstone and some kingdoms can summon undead hordes randomly through the game! so lots of stuff!
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