I tread carefully here, as this is clearly a issue for which a lot of people have strong emotive views. As I see it, there are two issues; firstly, the difference in the offences that cover the cases described; the other is whether motoring offences specific to whether or not death is caused are appropriate.
Looking then, at the range of offences we've seen used in the various cases, clearly the offences for driving without insurance and driving without a valid licence are pretty objective. But then we see a subjective distinction between two offences where death has been causes: "causing death by dangerous driving" and causing "death by careless driving". Actually this isn't the full legal picture, but such finer points are moot.
The former, "death by dangerous driving" carries a much tougher sentence, however in order to secure a prosecution, the jury must be persuaded that the driving behaviour was so aggressive, reckless and so inconsiderate that the person can be deemed a maniac and that the person probably needs to be jailed in order to protect other members of society. The latter, however carries a much lighter sentence. It simply covers driving behaviour that is believed to be deficient compared to the expected behaviour of a reasonable driver, but not necessarily actively aggressive or quite so reckless.
I don't doubt that our servants in CPS share our anger at the unnecessary tragedy of death on our roads, but the fact remains that the two sentences are very different. I'm sure that CPS prosecute using the tougher offence where they believe they can secure a conviction, and in the case of the driver who ploughed into and killed cyclist, this was used. However in the case mentioned by the OP, it appears CPS did not think they could secure a conviction using the tougher offence, and so used the lesser offence. I don't doubt the judge's professional ability to have issued the right sentence based on the offence, the defendant was accused of.
The other question then is, is the law deficient by differentiating motoring offences specific to whether a death or not occurred? Clearly in the case, it was not the driving behaviour as such that was at fault, but that the willingness to drive without a licence, which lead to a death. In this case, really the crime is best described as manslaughter. So why have separate crimes for causing death by driving? Well it seems that prior to this, it was difficult to secure convictions with a jury. Therefore the vehicle-related manslaughter offences would indeed be preferable. Unfortunately in this case, the lack of an offence entitled "causing death by unlicensed driving" may well have restricted the Judges ability to deliver a harsher sentence.
I hope this will help shed some light on the judgement, and provide some justification. I actually feel this is the symptom of wider problem, that people just don't take reckless driving seriously enough. I would push for society to remove the distinction between dangerous driving and causing death by dangerous driving, as I believe it is just luck that sets these apart. I would push for far tougher sentences for dangerous driving, irrelevant of whether or not a death or injury was causes, as I feel that 10 deaths a day on our roads are too unacceptable an epidemic. Driving is a privilege, not a right so I would push for a lifetime ban at the first sign of any reckless driving. Finally, I can only hope all who read this who drive will bear this and other tragic accidents in mind when driving and avoid any behaviour likely to cause harm.
