The "Buddies" System
Back to the basics; two are stronger than one and five are stronger than four. Since memory one we are taught to engage in the "buddy" system to keep each other safe. The "buddies" system promotes a public transportation expansion solution.
A no-cost or low-cost solution would be to develop a foot-traffic transportation schedule that meets at various checkpoints and times throughout the city. As mentioned, the great thing about an urban environment is the population density. People are going places and those same people are bound to go to the same places. Treat the system like a bus transporation system. Have routes that meet, leave and travel at designated times throughout the day. This gives women and girls the security of traveling by "strength in numbers."
"The Buddies System"-- The only thing that beats a super hero.