I've got a NVFR rating and all it means is doing the flight review at night instead of the day. It's not a big deal. From memory it costs the same but can be a hassle in daylight savings waiting until after 9pm to go flying.
I wouldn't fly do a flight in remote "black holes" at night but the NVFR rating is very useful and I've done a lot of flying at night. Often the air is smoother at night and the scenery can be spectacular. Doing the Melbourne City Orbit at night after fish and chips for dinner at Tooraddin is one of life's simple pleasures and never gets stale.
NVFR adds a lot of flexibility and is a very worthwhile way to get further training post-PPL. Recommended.