I searched coastal living here on Houzz and Pintrest. Pintrest had probably more suitable pics. Lovely ideas to choose from.

Without seeing the existing woodwork ( doors and skirting ) , I'd actually be tempted to redo that in a nice warm midbrown with a reddish tinge . Hogs Bristle is a pretty 'meh' sandy colour , and I assume colours like that are made so that something else becomes the highlight -- whether it be the wood features , the furniture , the artwork , or any other feature . To add white or off-white just doubles down the bland factor -- depending on the era of your house , if I had to go with Bristle I'd probably go with an Antique Red , or Ironstone , or similar ( even a Charcoal shade ) to add some colour without scaring anyone .

Your ideas sound great, you have a few mature trees, you could add textured sculptural foliage to highlight them, a water feature would look beautiful, a path to front door, instead of a straight path think large pavers in a staggered pattern to add a lovely different look, and a new modern letter box … gorgeous .. great house

Paint all trim monument to match roof and gates if that’s what it’ll they are. The facia above garage and all doors should be light to lift the place IMO. If you are replacing door I’d go timber. Otherwise if just repainting you are not limited to colourbond. Having said that look at jasper. Bunnings have colourbond samples I think. You need to put it up against your bricks