Whereabouts are you in SoCal...are you more inland or nearer the coast?
Schefflera is drought tolerant, but just to let you know..once it starts hitting the onerous triple digit, like any other plant, tips may burn..but they bounce back quite well.
Another suggestion, though I am pretty sure you have seen this plant all over SoCal..Agapanthus. They have that tropical feel, and lovely blooms, and quite drought tolerant too.
