If you ride with no lights at night it is definitely more dangerous.
If you ride with lights at night - I like it, and I feel like I'm more visible than during the day personally. During the day you're looking at a millions things, at night your lights are competing with far less visual noise to stand out as another person (obviously there's some exceptions, but I don't ride in Vegas).
The best advice I have for rear lights is to have two of them. Because they're behind you, if one goes out you don't know it went out and that you're suddenly in a lot more danger. 2 of them makes it very difficult to have them both go out at the same time.
Some of it depends on where you are riding, but just as I avoid places with lots of competing things to look at on my bike during the day (I don't bike through bizarre and difficult intersections for example), I also do not bike through visually noisy areas at night. But side streets and back roads at night are great, imo.