My commutes home are always at night. I avoid riding at twilight or whenever drivers can't see because the sun is in their eyes. I also avoid riding during commute hours. After 7 there is less traffic. After 9 pm, the stores close and there is almost no traffic. My commutes are mostly in the suburbs so no heavy city traffic. I love riding at night and will average 16-17 mph so I hit 20 mph. I have 800-900 lumens on the handlebar and another 300-400 on the helmet. I ride the same roads every day or I would likely go a bit slower.

I commute in the South Bay between Menlo Park and Santa Clara. Most of the roads have street lights but I have a stretch on Stevens Creek Trail which is pitch black. I take that a bit slower and use the light on the helmet to watch for critters (or their eyes) on the side of the trail.

There are lots of threads about headlights here and the prices span cheap to expensive. I'm a fan of inexpensive because replacement costs are cheaper. Total investment for my front light setup is about $100. That includes two sets of 18650 batteries and a charger.

https://picasaweb.google.com/1078559...94109830288354

For rear lights, I have three blinkies. There are plenty of threads on blinkies. The 2W standard blinkies run about $30-40. There are plenty of threads on red blinkies.

If you just want casual night riding you might be able to get away with less bright lights. If you are going to put in a lot of hours of night riding, you should be prepared to invest in order to be safe.