Satellites emerge in big cities too, they're called neighbourhoods. The extent of how far people are willing to walk in their daily lives will scope the size of a neighbourhood and that also pressures people to concentrate their daily activities within the same neighbourhood.

Public transit will lift the limit somewhat: people are willing to spend only so much time commuting or going to/from hobbies but with good public transit people will frequent other neighbourhoods on a regular basis. Public transit will be cheap as long as densities are high enough and that's why big cities are dense and have public transit. Large car-based "cities" aren't actually cities, they're just glorified urban office parks with people living in the suburbs: public transit will never work there efficiently.

The reason why you can't design a city is that a meaningful city can only grow organically based on whatever people happen to make of it. Commerce will surface when the place and time are right. Predesigning a neighbourhood will result in either a lot of dead space or a preformed area that nobody will consider their own.