As everyone seems to know how to solve the traffic flow system why don't you have a go at re-flowing the traffic from North to South and East to West to see if any valid solutions can be found, other than not using your car!
Closing off roads isn’t in my opinion an option and only increases traffic flow to our neighbouring areas.
Also attached is how I think could improve traffic flow, in addition to that:
• Width restrictors, two say two per road (flower beds).
• Narrower entrances to the roads (flower beds).
• Speed humps should stay, or be replaced by level topped humps.
I have not taken into account no right/left turns.
There is a blank JPEG for you to mark your one ways.