Thanks for the feedback tsudhonimh. Regarding the two tan walls. They are actually sandstone block walls that I built myself and when they and the rock is clean they are actually very similar in colour. See attached picture to give you a bit of an idea of a quick clean of the sandstone. Having said that the top wall is not structural and could be removed if it didn't fit the bigger picture I come up with, however the reason it was built was to keep the dirt from falling down the rock every time it rained and also to make it look somewhat more tidy. It is also somewhat of a railing as there is a dirt walkway and then some steps to get to the top rock. I have toyed with the idea of getting rid of all the dirt, surprisingly there is a fair bit of it and due to the weather in Sydney, most plants as well as weeds grow really quickly. I currently find myself about once a month removing weeds, which grow to about two feet a month in height specially in the spring/summer times. I do agree there are a number of somewhat flat areas, and I have been toying with the idea of multi-level terracing with a nice entertainment area. From the top rock I have a view of the city and the nice Australian weather means that we do spend a lot of time outdoors. I was hoping not to just do a boring timber balcony and the recommendation of John Lautner by makeArchitecture in the comment above has helped come up with some interesting alternatives. We have been looking at native plant options, we have quiet a few options for the area we are in and a lot of them such as the aloe vera and the other spicky plants you can currently see grow with no maintenance required except for some occasional trimming. Thanks for the suggestion to describe the garden as "rock garden" or "alpine garden" as that yielded some interesting results when goggling. I have also attached a photo of the house from the backyard to give you an idea of what the existing building looks like. We are currently planning on painting it white, as we have gotten some good ideas for similar barn style house on the Houzz site. This has definitely been beneficial feedback as sometimes it feels a bit overwhelming as it it not the standard backyard. I really wanted to have some ideas of direction before getting a professional to come in and design what the end product should look like as a whole. After I have that I can determine what I do myself and what I get a professional to do.

apennameandthata i don't know... vertical is more shed like style, while we still have a colonial style base and veranda. Dust will be an issue here (although its not so bad in that particular spot on a river, good protection from trees) but pressure wash will be regular practice anyway. Thanks for all your suggestions and I will take all on board, especially sandstone ideas. I don't this I want this house to look pretentious, but how can I describe that, I am after some subtle "wow" factor or something a bit different, but it must look like we knew what we are doing and YES, I want it to look like high quality build and not a transportable house or kit home. The house rectangle is so simple that I worry it may have that boring factor in its looks and that is why I am looking for some ideas. My problem is a tendency to overthink but I hope I will find a balance at some point :) At this stage I think: galvanised tin everywhere (or that zincalum), rusty steel posts, aluminum windows with timber look, sandstone features around main door and sandstone chimney. We had a big flood last year and the spot never goes under water, its on high grounds even though it is only meters from the river.

1. I'd probably start with removing the ornate lines on the gables. It seems a bit 'busy' and dated with the brick and gutters. 2. I'd also paint/replace the gutters to match the roof colour or even the garage door colour. Gutters aren't an architectural feature, so no idea why they are terracotta. These 2 things will calm it all down. You could consider texture-coating the board of the upper storey. It's a colour-embedded acrylic render. No painting for 25yr. It gives you the look of render, and can go straight onto board like you have. Unless you have rot or other maintenance issues with it that you need to replace it.

The silver will look quite good with your colour scheme. I would probably change some weatherboard for Scyon Axon just to change it up a bit. Also use Scyon Axent for architraves and wall corners. Don't forget eaves and veranda ceilings, etc. as a really nice looking feature use HardieGroove or maybe even some timber to break up the acres of painted surfaces.