The idea of ​​public transport in the game.

[3dmodel]

Perhaps something similar has already been proposed on the forum, but I did not notice.
This can be a separate option for the City Economic Simulation DLC, or in the game itself. It can also be operated by the city or partially by private companies.
Settings in the menu:
1. Enabled Disabled
2. Impact on the city's economy enabled disabled: if enabled (easy, medium, difficult) with increasing difficulty, the more people cannot get to work, the stronger the negative impact on the city's GDP.

Transport can be metro, buses, electric transport and airplanes, etc.
The implementation might look something like this:
1. The same as implemented in banks. Transportation income - all expenses (maintenance, salaries, etc.). To save space on the map, place transport stops right on the road (if possible). Add to this the traffic congestion factor the more stops the better the quality of service.
2. Through factories. Factories receive, for example, tickets, fuel and vehicles, and produce a unit of service.

You can also add a taxi service and car rental.

[mrgarrettscott]

With the CES DLC, I can understand why there might be some appetite for this feature that you are proposing. I just think it is way outside of the realm of Capitalism Lab. Outside the of GDP factors, I think the CES DLC is outside the scope of Capitalism Lab. There are many games that do city building much better and games that focuson on building and managing public transportation while leaving the city building elements out. For Capitalism Lab, its focus should be about managing a corporation from the top down.