Want to renovate our back garden

We are very inexperienced gardeners/landscapers and would appreciate any ideas or advice.

The back garden (and yard) is in desperate need of some love. We currently have a bottle brush tree and two grevilleas. I want to keep them as we have a lot of lorikeet visitors, but do need to prune them back again. Previous owners planted them off centre.

We would ideally like to have colourful native plants that can tolerate shade and more damp soil as rain tends to collect there. We will need to replace the bricks lining the garden bed and fix the fence.

There is also a section next to the playground that is hard clay soil. But any recommendations there would be appreciated as well.