Ideas for garden spruce up please (WA)

Kind redditors, this brown-thumber with no sense of style/decor would greatly appreciate some ideas on what I can do to make this sad garden bed look better.

My living area looks out to this. This fence faces west, but is shadowed by the patio in the evenings. Garden bed is just under a metre wide. Reticulated. Due to health reasons there are extended periods where I have to stay indoors. I’m in Perth.

I had 2 gorgeous westringa bushes on each side of the centre drqcena. They died off suddenly after thriving for a number of years. They were perfect as their leaf drop were never an eyesore when I couldn’t tidy the area up. The replacements never thrived.

What shrubs are similar to westringa with regards to care and leaf drop? I’m wondering of gravellias or viburnums would work. I know I’ll need to improve the soil before planting.

I’d like to keep the agaves on the left and the sad looking lemon tree on the right, but everything between is fair game. I’ve also bought a dark grey paint for the bricks.

Lastly, I’m hoping to put up a bamboo screen to cover the fence and level up the sloping fence line. How does that work with regular watering from the sprinkers? Wouldn’t the bottom bit just rot after a awhile?

Clueless. Send help and ideas please.