Is there data that can evaluate the pluses and minuses of a less homogenous council? For example, data that would show if you have regional or district elections do you have a much more contentious council advocating for its own district rather than the entire city?

City staff  is not aware of any quantitative data that addresses this, though there is qualitative scholarship and case law recognizing the possibility that districts could lead to more concern for one’s district at the expense of a “big-picture” view.  However, the extent to which this is true varies by jurisdiction.