I think you should cross-post this to not only the CA gardening forum, but also the Landscapers forum. Bahia (screen name for David Feix who is an amazing professional out of San Jose) can make up a list of appropriate plants for you almost right off the top of his head. His succulent landscapes are fabulous: colorful and water-thrifty, way beyond dull cacti. You should do a search: he often posts photos of his recent projects, and they are always spectacular.

I love oleanders but watch out for the Glassy-winged sharpshooter, which has devastated entire stretches of oleander plantings in Southern and Central CA. It's why Caltrans no longer plants oleanders on median strips, since the GWS also attacks vineyards.