I don’t know whether you have done your painting or not but with your dark furniture and existing windows I would paint walls light warm grey and 150% strength same grey colour on the architrave .something different and grey , yellow and brown look good together.

Hi, we had the charcoal next gen decking installed 6 months ago for similar reasons - fully exposed deck, no time to maintain. Went with charcoal after much debate as we didn’t want it to look like fake wood but rather something different and modern. We’re happy with the outcome

Dulux whisper white. Get a sample pot, paint a large piece of cardboard and see for yourself.

There are lots of paint manufacturers apart from Dulux, and hundreds of whites that it could be. Unfortunately the natural light in the photo, the type of camera, any photo editing, and the adjustments on your computer screen make it impossible for anybody to say with any accuracy what the colour may be. The only way to find the right white is to get samples and make your own judgement on site. I always think that Perth light seems stonger and brighter than Sydney light - possibly due to Sydney's airborne pollution in the inner city? There are lots of online resources by various paint manufacturers about choosing the right white, but don't make selections from an online digital image as it won't be accurate. Best of luck, Dr Retro of Dr Retro House Calls