If you are already familiar with the game and you would like to have more fun, you can go to options and in game settings select Expert Mode.
This mode gives you access to all kinds of areas at once - from small sections for workers' houses to plots for huge multilevel office buildings. This is good but on the other hand - not necessarily.
A good aspect is the possibility of building immediately medium density zones - so we avoid demolition of old buildings in order to build skyscrapers in the city center. However, one drawback is that when you build a high density factory, you need a lot of different types of workers immediately.
The workers will immediately begin to demand everything - lots of shops, schools, police, entertainment etc. And you can access the building only after reaching the relevant thresholds (e. g. 5000 citizens). An additional drawback is the price of new zones. Plots can cost thousands of credits per item and you have only 400,000 of them at the beginning.
However, the expert mode's advantages greatly outweigh its disadvantages. The possibility to build higher density zones results in much sooner arrival of new people to the city. But remember about all aspects of such rapid development - more people at once means faster emerging unemployment and higher requirements for trade and entertainment.