I've lived a few different places, also working in transportation engineering. I personally care a great deal about accessibility, and would much rather delay cars slightly than pedestrians (for numerous reasons). For example, when reviewing traffic control plans, etc, I always make comments or suggest changes along those lines. But ultimately, it comes down to what the municipality wants to prioritize - unless there are safety issues, it's hard to do more than suggest and push for something better.
If you want to make a difference, making comments (about ongoing projects, particularly) will tend to have more impact. For something more systemic (like light cycles deprioritizing pedestrians), I found the best solution was to move to a better city.
If that's not a solution for you :) then another option you might want to consider is having a meeting with your municipal (or even higher) level elected representative - invite them for a walkthrough of a more problematic space, and try to explain the issues and possible solutions as calmly/rationally as possible. And without attacking car culture directly, as that tends to get people defensive.