Just 3 of many ideas to reduce traffic:
1- Reduce the quantity of 4-way stop signs. Better yet, install roundabouts.
2- If we are building a smart city, shouldn't we also trust our citizens to make smart decisions? Allow right turns on red.
3- Installing traffic sensors which increase the flow of traffic. Companies like http://miovision.com would allow us to do this. At the very least, install traffic lights that are timed with one another!!