I haven't played the latest version of the game, but the easiest way to achieve a nice SC4 city with full of shiny buildings, cleantech and high approval ratings was to levy much higher percentage taxes on low incomes than high incomes (thereby driving all the poor out of your city). And without those pesky low income Sims your city would continue to do just fine. That's almost as much a of a far-right fantasy as solving suburban crime by placing police stations every six blocks.