If I'm reading your post correctly, you're asking by what criteria do we measure or evaluate local LE success. If this be the case, then there are two broad categories within which we must have criteria.

The first is most common, easiest to measure, and you've already mentioned. Response times, arrests, traffic citations, etc are all criteria used to evaluate category one: organizational competencies. Much has been written about these and many are most familiar with these, so I will leave them alone.

The second category is organizational legitimacy. These are more qualitative in measure.

1) Evaluation of Organization Demographics: Who is applying and who is being hired? In many cultures, where one or two demographics have dominated the political/government landscape, examining who is applying will show how the population views LE as both profession (can I make a living here?) and organization (is this a legitimate organization, i.e. one where I can work at all?) Mandated diversity requirements are of little utility; a natural trend toward diversity shows an organization that is viewed as legitimate. Just as important as who is applying is who is being hired. This shows the organization's beliefs on diversity and population inclusion. Hiring diversity will increase perceived legitimacy and application diversity. It works much slower and much less effectively the other way around.

2) Increases in Calls for Service. Are people calling the police to report crimes? In cultures where justice is often viewed as a mix of honor and vengeance, increases in calls for service are a sign of major shifts in the population accepting LE as both legitimate and competent.

3) Increases in Voluntary Reporting of Crime. This category is distinct from calls for service: calls for service typically involve criminal activity that directly (it happened to me) or close to (it happened on my block) the caller; it has impact on their immediate life. Voluntary reporting are calls regarding information about criminal activity that does not typically affect the caller directly (think: TV tip lines). This is also a measure of acceptance of legitimacy and competency, but important for the fact that many people will call when they need help, but fewer call when someone the barely know or don't know at all needs help. It shows that the population accepts that their involvement will be kept - where appropriate - confidential. That is, the police can be trusted.

4) Population Surveys of Perceived Police Legitimacy. "Survey" can include both formal and informal reports. I've remarked previously that it amazes me we often focus heavily on "quality of life" policing but have almost non-existent qualitative metrics. It should constantly be asked of the population: "How are the police doing?", "How are we doing?", "How do you feel about crime in your community?", "Do you feel safe?" and the many variations of these questions. Quantitative statistics are undoubtedly useful, but as we've seen here in the US they mean little if the public doesn't perceive them to be accurate or the police to be legitimate. Of course, once these surveys are conducted, the responses must be acted upon.

These four criteria are certainly not an exhaustive list, but are required for evaluating local police performance.