Thanks for everyone's help. We have decided on Whisper White with standard decorator's white for the ceilings, as suggested by you and the painter. I also found this earlier post about white paint shades to be very helpful for others facing this dilemma! https://www.houzz.com.au/discussions/3019158/which-white-is-right

Hi rachemacdonald Natural white is one of my favourite interior whites. It's not too creamy but still warm and not cold and sterile. Use low sheen on walls. Use half strength on the ceilings in a flat finish. (The ceiling acts as a reflector to bounce light around the room.) The trims - arch, skirts, windows and doors can be half strength in a satin finish. This will modernise the space and make it feel more spacious. Best wishes.

Thanks. House completed a while back. Builder did all trim and doors in vivid white. Ceilings in ceiling white. Left it to them.

Try dulux snowy mountains. Just hope you plan to bring some colour and textured elements into space. With the tiled light floor, the effect might a bit cold.