Any little jobs like cracks in walls, painting etc definitely do so the house looks shiny and new again. I know our house after only 4 years needs a bit of TLC

I agree with the others re decluttering, although tbh your house feels spacious and airy already, but set your spare room up so potential buyers can see it as a bedroom (can you move all the office stuff out temporarily?) and pack up as much as possible to give the illusion of more space not only in the house but in the cupboards, storage areas also.

Chuck the breadmaker on so the bread is cooking during OHI too

Little things like setting the dining room table (not over the top) look lovely and give a nice vibe and I also think that in Australia people value the outside space of a home just as much as inside so you want to make sure they can visualise how to use your outside space - eg sitting outside enjoying a BBQ with friends etc

Give the gardens a good trim and keep them tidy and use your fabulous lighting to show the house off at its best