In the straight part of the bed that runs from the street to the crepe myrtle, I would plant leptospermum to make a low hedge. It would be worth going to a real nursery for those, to find a variety that won't get too tall...plants are like babies, they look cute in their little nursery pots, and the quickly turn into teenage thugs, eating you out of house and home!
I would plant something sculptural at the edge of the street, like agapanthus or kangaroo paw. If you do agapanthus, they have white ones.
Definitely white groundcover roses under the crepe myrtle tree.
How many hours of sun do you get right up against the house?
A bed of different varieties of lavender in the bed in front of the walkway, and if you like the idea of some small trees flanking the front door, how about some citrus trees?