[Thor]

I think its only normal that the higher you want to get in happiness, the more expensive per point it becomes, I maybe more of a problem with the last 2 houses costing respectively 20 and 40 more millions to get more happiness.

although they give 250 and 500 more, it is just a very huge jump in cost.

From midlan house to villa is 5 mils, from villa to arcology house its 5 mils, then boom! 20 and 40 mils to upgrade again.

Maybe make it 10 more mils to get to the 1500 happiness and another 20 more to get to the last house and make it 1800 instead of 2000?