Well I'll have a try
To be really fair surely the congestion charge should be linked to the CO2 emissions in a way that doesnt have the arbitrary cut off of 225g/km of CO2.
Who came up with that figure anyway? And why? Why should someone driving a 224g/km car pay much less than someone driving a 226g/km car?
Surely the charge should be in direct proportion to the level of emissions? i.e. 1 pound for every 10g/km.
And then you would need to take into account the number of people in a vehicle. i.e. a minibus with 10 people produces less emmisions per person than 10 people driving individual (though fuel efficient) cars.
Problem is though it'd all get very complicated. Then you'd need a workforce, all of whom have to drive to work, working in a heated building (which will, of course result in increased pollution).