Credit to
https://www.trueachievements.com/gamer/Yui+ShojeiI saw this in a comment on another guide and thought it needed more exposure.
I did this with 125k city.
- dezone all industrial and commercial
- use only office zones and residential
- max out services budget (medical, police, fire etc)
- total coverage with schools to create high educated workforce
This removes a lot of noise, traffic and pollution. I was running with nuclear power and garbage incinerators out of town.
Then sit back and wait a few hours for 5 years to roll by