I think the first thing to think about is the see light, vs. the be seen light.

Be seen lights are fairly easy. Your red rear light is a be seen light. I really like the pretty wheels with colours, but I don't think I will do them right now.

Your SEE light is a different matter. Some people who are riding in the country can get by with very little light because your eyes will dilate and you will be able to see in the dark. Those in the city need to be able to look at a car's lights on bright and still be able to see the road in front of you.

Photography is not the way to judge a light because you adjust the Fstop and ISO and good lights look bad and bad lights look good. Only judge the lumens.

I was riding the other night with a Fenix headlamp. I am not sure how many lumins. It was one of the original batches so maybe 250?. This was find on a dark trail, but pretty useless when I was beside the road.

Last week I was riding with a 1000 lumin flashlight. This was nice. I could see the path even with cars pointing lights at me. The on coming bicyclists hated me because I ruined their night vision, but then again they were riding with be seen lights, not see lights. These flashlights use 18650 cells or 2x123 batteries. Great setup.