Flying at night is wonderful, but.......
The last thing I will do is argue for any reduction in privileges in what has already got to be the most ridiculously tightly regulated activity humans can do, but I would not allow anyone I care about to fly at night unless they were able to fully fly, navigate, and land on instruments (practically, not necessarily legally).
Unless one sticks to local bimbles on very clear nights, it's easy to get into IMC en-route. Kennedy anyone? It's also easy to end up over countryside where there is nothing lit-up, and even where there are lights they often bear little relationship to the size of the village/town one is expecting to be there. Especially late at night when street lights get turned off.
Few PPLs come across these things because few of them fly "properly" at night. Most PPLs pop up for a local, just after the official night time when there is still plenty of daylight, often just to get the required logbook entries. Most airfields aren't open late enough anyway, for the last remnant of daylight to vanish.
Proper night flight is pitch black, basically solid IMC. Nothing to see below, no horizon. 100% instrument flying, 100% instrument navigation. Dead reckoning (the official nav method taught in the PPL) is even more useless than at any other time.
I can fly at night and have all the logbook entries including the FAA PPL and IR cross country requirements which as it happens were done at night and in IMC, but unless I have to get home etc I don't do it by choice because there is no point in closing off the chance of survival in the event of an engine failure. It's a bit like flying, VMC on top or in IMC, over mountains covered in cloud; I've done plenty of it in a single but would not do it by choice. At least with mountains, provided one is well above, one can use the GPS terrain data to glide into a valley and bottoms of valleys are usually clear of cloud. But at night, unless it is a very bright one.....?? One may as well fly over water with no life raft.