I bought the game a few days ago, and I like it far more than the sim city which came out in 2013. Traffic can be an issue, but public transport (buses, mostly) and proper roads usually do the trick.
I have a few congestion issues on the main avenue heading from left to right, mostly because there are numerous junctions. I have policies enacted to force lorries carrying large cargo to go around the city on a more efficient road.
The road in the foreground connects to the regional highway to the right, and stretches around the most populous area of the city, towards the industrial area.
There is some ore and a regional train track to the right of the map, so I extended over there to set up a second industrial centre and some high-density residential zones. Once I have 16k residents I'll be able to have a facility to clean sewage water, so that ugly purple smear will soon be cleared up.
A good transportation network is vital to a congestion-free city, so I have routes going through all the major areas and then linking back to the bus station, which is why so many people are there.
This is the dual carriageway leading to the eastern sector of industry where the ore is. The road network is vastly more efficient here...