It is a very nice topic and concern. As many things in aviation, it is important to mitigate any possible thing that can go wrong.
I basically agree not to encourage NAV at NVFR with current (old) SEP AC, a Cirrus would be better no doubt. Flying only day VFR would be better however, it is part of the training for PPL aspirants for CPL/IR pilots.
PFL and EFATO are not being flown as part of the training, we do brief the students during our theoretical ground school designed for NVFR. The risk of practicing this is quite high.
On ground we go through different scenarios of PFL, different terrain types in the area to be flown and possible hidden hazards (lamp posts, fences, dark buildings, trees, electric wires, to name a few, the list is long), we go through the last seconds before landing/possible impact where we may get a hint of obstacle with the landing light few seconds before giving us a slight quick chance to do a sudden turn to avoid a head on impact. We do analyze the possibility of considering the ditching on a neighborhood lake and the ocean with the possible consequences of doing such a thing (obviously depends on the grounds to do so, the outcome must be better off than a high/irregular terrain). The importance of calling a Mayday with clear concise information (coordinates, etc)
We do however practice glide to land in order to get the student to feel how the aircraft glide without clear clues from the outside.
Regarding ALTERNATOR failure, TOO’s experience was very nice to be shared. On the emergency section during the Ground school we cover many “what if” situations.
We make sure the students don’t show up for NVFR without a non glaring flashlight and a backup white one, during the flying part we turn off the cockpit lights and we continue with the flash lights to simulate an electrical failure, we also include the flapless landings and without landing lights.
We brief for the lost comms procedures and at some point we request the controller to give us green light on final, so the student gets to experience those lights we always see in books but never got a clue how they look in real life.
Another concern is WX deteriorations going unnoticed, we ask students to update ATIS every one or second FREDA checks, depending on the night, paying attention to T/D, clouds formation, QNH.
On a NAVEX once we got caught inside a cloud due to weather changing rapidly and not forecast, even going unnoticed to me (that AC didn’t have strong beacon light nor flashing wing strobes) from that night I make sure that every now and then (or when suspicious of clouds formation) I make use of landing lights for few seconds, if you are in the proximity of a clouds the white light will show you the hazy vapor ahead.
Fog formation can also be a concern, hence the periodic checks on TD.
Another night, while doing TG on a clear night, fog made the airport go IMC, if we were outside the CTR we would have been forced to divert, as we were visual with the runway we continued for a full stop.
Fog can cover the dark ground and go unnoticed, I always make sure my students are very vigilant with the weather, pre flight and during the flight. Any weather deterioration forcing you IMC is an emergency (for VFR pilots flying at night). SEP Engine failure at night after WX or fog?.... difficult to answer. Be ready to mitigate.
Disorientation, general handling practices, partial panel is also important for the training.
Smooth flying and to avoid overbanking/steep descending is imperative for me while teaching NVFR.
Illusions and body reactions are very important too, they may be little at starts but if goes unnoticed may grow into an avalanche effect, it is important to recognize them.
The NVFR is a serious training that it is only done in 5 hours. Ideally should be bridged with the IR under my opinion from the training point of view.