I personally think the cladding would look nice and be the easiest to maintain. We also live on the Gold Coast and have a brick house that has been rendered (not by us) and, to be honest, it is not particularly low maintenance (if you want it to stay looking good that is). It is prone to leaching which leaves ugly stains so regularly needs retouching with the paintbrush. It can also develop small cracks in the render due to temperature change and movement. However, the most worrying thing for us is with regards to termites. If you render over your brick on the lower half of your house, it is highly unlikely you will see the telltale "mud" they leave that indicates they are trying to gain access into your house (they climb up in between the render and the brickwork). I would be trying to keep the exposed bricks in preference to rendering over them, particularly if you have a garden bed up against the house anywhere.

The charring of wood as a method of preservation is nothing new and was known to European and Mediterranean builders as well as Asians. I have for years charred the bases of deck posts and such as a rot preventative. The practice is mentioned in John Fitchen's classic book Building Construction Before Mechanization. Some of the samples of this shown above are a bit crude. The most beautiful finishes of this type are rather labor intensive as some of the char can be brushed back off to some extent to reveal wood grain. The planter shown below has been coated on the interior with linseed oil, blackjack and turpentine and then set alight with a roofer's torch. The finish is cooked into the wood producing a carbonized insect and decay resistant surface. It gets filled with soil and so the char will be seen only at the edges.

The weatherboard look suits so stay with that but maybe a recladd in an FC Weatherboard. Have a look at Scyon Linea. Which is a high performance version of Fibro Cement. Also use some architraves around windows and doors. A repaint will make a big change. I'm not a fan of blue blue I'm more a grey so look at 'Windspray' or 'Timeless Grey'. Paint the new architraves in white or 'Shale Grey'. One other change I would make is landscaping. Have a professional do a design for you this where you'll really make the property your own.

Got my answer - non combustible material such as, natural stone - marble, granite or concrete etc.