229 Hours of Gameplay and yes i found out a way to stop the traffic jam………….so it seems to be that the cars are not the biggest lag issue 🙂
1. upgrade all Streets in town to Maximum size with bus and tram line
2. try to get above 70% linefrequency passengers
3. enjoy the reduced traffic
4. tested in Citys with up to 1400 people with tram lines from town to town with
Town A to B with 20 Trams and the same in the other direction from B to A with 20 Trams (6Stations per town in a circle spreaded around the citycenter)
5. negative Points it will be laggy sooner or later 
and you have to spend a lot of Money for City micromanagement
greetings Markus
