Hi! Nice model, but the materials could definitely use improvement like you said. First thing I would do though, is add some more dynamic lighting / environment. Right now it's too flat, and with these flat viewing angles as well it's quite hard to tell what the material is doing and therefore do any meaningful work to it.…
i dont know much about gun control, but why hoping someone to bring gun and stop the guy not everyone want to bring gun or even smallest blade everywhere or see someone bring it in public.
I would model the intersections beforehand, and then create the roads with modeling a section and extruding it along a spline (which you can create on top of your plane mesh as reference), connecting your roads to your intersections should require a simple bridge at that moment.