That's all fine and dandy, but I need strategy help with the game as it currently runs.
If you care at all about the UP. Population = Vote power.
Cities are more used for adjacency bonuses more than for driving up population. Unless someone can tell me otherwise the usefulness of hospitals and other growth buildings are dubious at best. If population gets too high moral suffers, and you get penalized in production and EVERY kind of stat growth. So then you have to waste more precious slots on entertainment centers.
A rule of thumb I follow is, any base 12+ planet gets a single city. My capital gets two. And I make sure the city is directly in the middle of as many important buildings as possible. Any base 20+ planets can use an extra city too. They've got lots of land to slap them in the middle of buildings. You basically need max terraforming tech to make cities viable on lesser planet, and even then the 12+ ones will be better off and more flexible.
Also if you dont mind mods, make a "GalCiv3GlobalDefs" xml file in notepad and throw it in the folder Documents/My Games/GC3Crusade/Mods/(whatever name you want)/Game
I'm not sure how much of that you need, but the PopulationToProduction is the actual value. Default is .5
This tiny change makes population more valuable.
Well something that would be more realistic, but hard to implement. Is limited need for things. Say what you want, but there is a limited number of goods, and services on this planet at any given time. Your right the number of qualified individuals can increase, but basically you see a shifting of who provides the resources, not an increase of resources. This is dependent on factors galactic events, but once a certain number of things get filled. New ones only waste space, cost money, and eventually close. Basically the faction with the lowest economy would get the jobs. The faction with the highest economy would lose jobs, unless they lent money which in turn would increase the economy. Trade would need to be more important. That still is more significant than population. This would cause fluaction of factions, but would be more realistic.
It's already represented by approval. High pop = low moral. Entertainment center can just be thought of as a space mall. Buy food, luxuries, watch games, movies, whatever there.
There just isnt any in game reason to go for as high of a pop as possible anymore. Which sucks. Maybe high population shouldn't drive manufacturing up as much. But it DEFINITELY should give you better tax income and you have the potential of more researchers for tech advances. Legions for attack and defense should also be tied into population instead of social production so the AI can actually defend 90% of their planets. Somehow has to be working on those big ships flying around in space too, why isn't pop deciding your ship limit as well?
Pop is still very important in a scifi setting on a galactic scale. The Synthetic races should be scarier because of that fact.