No the idea of elected police commissioners is not a good idea. Nor is the idea of elected Regional Assemblies (soundly rejected - much to John Prescott's dismay - by the people of the North-East).
The system of local police authorities, overseen by the local council, is also a nonsense. Chief Constables should be appointed by the Home Office to carry out policing in line with national government policy and they should be answerable to the Home Secretary. You only have to look at the motley collection of political has-beens and never-has beens to realise that these posts are just another way for such people to collect £100k (plus expenses and pensions, natch) of taxpayers' dosh. (Of course, once in post they will all have to have a "small budget for administration" which will run into a few hundred thou more, thus enabling them to employ some of their relatives). And this from a government committed to implementing cuts.