Coneflower/Echinacea is an old favorite and can be completely neglected, they will grow anywhere in full sun. Even in poor soil. They also spread nicely. Looks nicely when paired with Russian sage - blue and pink
Ocotilla - This is a really cool neutral plant that adds a vertical element and height to the garden, yard, and landscape. Other than when it is in bloom the Ocotillo is a grayish neutral color that goes well in most any Southwest desert garden.