"...What you're saying is that if I speed, I should pay, say £200, and boy racer in his clapped out death-trap Nova if caught for speeding should pay £20 (figures plucked from air)..."
No, that isn't what I meant at all. Of course fines would be subject to a minimum so he wouldn't get a £20 fine 'cos he was unemployed and only 17. He'd get £200 or £2,000 or whatever and/or go to jail for not paying.
The idea was that the sliding scale should slide upwards, not downwards to ensure that all criminals feel the pain.