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With low voltage DC systems you are fairly limited in how far you can run the wiring before voltage drop issues begin to cause problems. BUT low voltage DC systems are much safer since under ~50 volt many electrical codes consider to be safety low voltages, and generally not an electrocution risk. (Yes, if both conductors were inside human tissue there is a higher risk) Also many low voltage DC systems are run ungrounded (unearthed) where you would have to make contact with both conductors for any current to flow. See - https://www.filebuzz.com/findsoftware/Voltage_Drop_Calculator_Metric/1.html

The 230 VAC system has a much longer distance it can be run for the same wire size before voltage drop issues become a problem, but it also has shock risks with contact with the hot conductor and ground (earth). As for positive points, almost any normal household load can be handled with a properly designed 230 VAC system.

In general LED type lighting is available for both systems, but larger loads above say ~100 watts are fairly rare for 12 VDC systems. So 12 volt systems can handle lights, TV's, radios, small fans, and some very small electrical refrigerators and such, but aren't practical for cooking appliances, pressing irons or other large wattage loads without specially designed systems with very large wire sizes.

Larry Bentley EWB-USA Energy Content Committee