I had my car completely rewired by a professional 4 years ago. Might be the best investment I have ever made in a car.
Guy who did the work told me with all new wiring and good grounds, properly sized battery cable to the back, etc, etc, etc.. I would be pleased.
Other than for a while popping alternator belts off which several times killed the battery( problem solved by new alternator bracketry), I haven’t had a charger within 100 yards of the car. Starts like it’s 16 volts, run fan and water pump between rounds, zero issues.
Most all the stuff mentioned above, hi amp electric fans, electric water pumps, fuel pumps, msd boxes, etc, have been around since the ice age. Mine is 12.5 compression.
To me, having had issues pre getting rewired, I would look at wiring first. If it’s golden, the chance of any issues with a 12 volt system are remote, in my opinion. 16 volt can well be a band aid masking a deeper issue( poor wiring)