One thingnthat I would like to see is for the emotionless trait to be fixed. Tis supposed to provide a flat +20% bonus and stay there. Instead it merely freezes the pop happiness at current level.
I had thought that this bug was fixed but I was playing a SE4-1.78 Proportions game and managed to take an enemy homeworld after a sustained siege. Imagine my supprise when I noticed that my spoils of war were frozen at -100%!!
There was nothing I could do. I tried replacing the population, and even tried scouring it with neutron bombs, but in the end I just had to scrap it and move on.
My wrath was legandary.