In the last few years, I was able to add "Streets", and although a fair amount of time and effort was involved in building them into my city, I really like the effect. For the life of me, I don't know why they don't include operating headlights in their vehicles, something that is beyond my skill level to retrofit. Oddly, a couple of companies offering operating headlights in their vehicles, yet the vehicles are static?
Here's short videos of nighttime scenes. The "clunk" towards the end of the 2nd video is the steamers colliding at one of my crossovers...that's why I had to shut down power asap. As I get older I find it more and more challenging to drink and drive trains and cars on the layout at the same time 
Updated video showing trains and "Streets" vehicles - towards the end of the video (3:12) there's a scene of the "Streets" intersection with a RK trolley stopped on the bridge. In the future, I'll try to make a video of cars passing through after the trolley goes through, or vice-versa. The trolley line is a "Streets" line as well, so I run cars on it from time to time.
https://www.youtube.com/watch?v=f8Wdz5shdRE
Video showing just "Streets"
