A simple trick I learnt : How to find the exact complementary colour. Get the colour in a strong light.,,,sunlight preferable. Isolate it and stare at it intently for a minute or so, Close both eyes and see if you can see a colour..."reflected" on the inside of your eyelids.....THAT is the colour that will be a good complement for the one you want . In this instance, since the colour is mixed...you might "see" several. Looking at this electronic colour...( not the ideal scenario)...but.what I see is a light greeny/ grey, a swatch of the colour would be easier to do this with. Put the swatch on a white background and....stare,,,,so..."light grey" is close but maybe with a touch of green. Hope it is successful.

I agree to do your own thing! There were 10 feature walls in our last home, only two of which were painted same colour and that was because the rooms were opposite one another from the entry. In our current home, the only feature walls are in the theatre room, and we painted all the walls and ceiling. Walls are a deep plum and the ceiling is black (all matte).

Looks good. Before I read through discussion, I had these thoughts. You could look at painting on the front of the wall only, not in the porch/entranceway area underneath, double strength of main colour. So you could as an option get a test pot of Dulux double Self Destruct or even triple. I would not use Monument, or similar to the roof color as it will disappear into the roof. I also think the front fence would look better painted a stronger colour from your existing but as it seems it has just been painted perhaps you could do that, when and if you liked, to cut down expense. On the Dulux website they also give you colours that look good with Self Destruct. (Picture below). Another option is look towards going bold like a strong blue or blue green. Something like in the picture. That's my feature wall, Resene Billabong. ...or a dirty purple or a blood red. It's starting to get really personal of what your tastes are. Perhaps you could Half or Quarter the main house colour in the entranceway so it still flows but gives you more light. Exciting stuff!

brick wall so no option for cavity sliders gas heaters are already in that middle wall as marked, old heaters i think i need to service them as not sure when its serviced last also has two split aircons on both rooms on the far end no weather seals on entry doors, i can feel cold air is coming under some doors, where can i get the seals or is there someone who can come nd check all doors/windows and seal them tin flat room with not much space in between. I think there is insulation in the middle if not its very hard to do anything without opening up the roof sheets. We have double roller blinds on one side. No curtains on patio door(kitchen).