Is it a dwarf flowering gum or a big one? Many gums affect the ground beneath them, not allowing other plant competition to grow there...except azaleas, rhododendrons and other acid loving plants can do well. Another idea is to think of some native grasses, there are some excellent decorative cultivars now that are very hardy too. Some of the small lomandras could be planted in clumps of varying heights and colours, also dianella silver streak would be pretty.

If the murraya and other shrubs are growing well then the area must get sun and should grow grass. If it is a high traffic area you may never be able to grow grass in the area they constantly walk on. To renovate if it is sunny and neglected - spike with a garden fork all over the compacted areas put down some fresh lose topsoil and replant or turf. The only answer if it is constantly used is to put concrete or pavers down. If you haven't watered lately, water regularly and fertilise you will be amazed if it is a running type grass. Grass likes regular water and fertiliser .

Hi Brett, this is an image from Outdoor Establishments in Sydney, one of their Mosman projects. Maybe you can ask them? I'm tipping Dianella or possibly Liriope. Leaf blade is too wide to be one of the more likely Lomandra's.

Wow amazing advice - thank you!! We are in the mid-hinterland on the Gold Coast. :) Since posting we have planted out the back strip with a mix of Vibernum, Chinese dwarf bamboo, elephant ears, Xanadu and ornamental grass. We still have both sides to do yet and it feels like it will never end! Unfortunately our garden beds were edged with pavers at build stage and we aren't equipped to rip them out to widen the garden beds now. but I am considering culling the mulch in some areas on the sides and putting in feature sections with Riverstones. I love the idea of using water feature/bowl and will try to incorporate one. We went and bought 9 golden cane palms which we haven't yet planted due to some posts online about the root systems and them being problematic, we are thinking about maybe putting them along the retaining wall, any ideas how to manage the root growth? We thought about keeping them in larger pots and planting around the pots, has anyone seen this executed well? Updated pic attached. You can see a bush fire that went across the hinterland yesterday, bit close for comfort! Also the palms we are thinking about in bags against the wall. PS - Whoever would have thought that turf is so hard to keep lush! OMG thats a whole other post! hahaha