Had to look those up, but are those Mediterranean Palms in the neighbor's yard? If so, do you want the same thing within a few yards?

Unless you need the palm fronds to shade the front window, I'd accent the wall by putting in a selection of succulents. Obviously, I'm totally unqualified to suggest plants for California, but there are some on the forum who definitely are.

Personally I would not try to cram a Chamaerops humilis into an 18-24-inch space. It's a nice palm, but it is suckering and the spiny trunks are a piece of work to trim. It will be a bit cramped in that spot. Why not put it out in the brown spot on the lawn and put something that goes with your theme in the planter? Surround the palms with large rocks similar to the wall - not in a circle, more of an irregular heap, and throw in some blond grasses among the rocks to give it some life. Combine two or three different heights and colors of Anigozanthos (kangaroo paws) in the planter. They are drought tolerant, won't mind the heat and cold, and mixing clumps of a tall variety, perhaps in yellow, with clumps of a shorter variety, maybe orange, red, or purple would put some low-maintenance zip in your scheme.

Duluthinbloomz4, those palms in the picture are pygmy island date palms.

Mikestecker, from the size of your neighbor's palms it seems you don't see 20s or 30s too often. Those palms would be toast if you saw those temperatures every year.

I would use the blue form of the mediterranean fan palm. it is much more attractive and would set the stage for using many different succulents. You could then plant different plants using a silver/red/purple color scheme.

I would actually expand the plantable area around the wall to follow the line set by the cement walkway coming from your driveway. You could fill the area with grays, reds and purples. Many succulents could lend those colors and many drought tolerant plants could fit the bill there. i could suggest user friendly agaves like Agave Attenuata or Agave Vilmorniana, aloes like Aloe Reitzii, Aloe Plicatilis, Echeveria Glauca, Lavender, kalanchoe.

Can you plant anything inside the space enclosed by the wall? you could plant the med fan palm there and use some postrate rosemary to cascade down the wall. Also, have you considered using a couple of tree aloes instead of a med fan palm? Some species to consider are Aloe Africana, Aloe Speciosa, Aloe Alooides, aloe arborescens, aloe Marlothii, Aloe Ferox, Aloe Barberae... there are many species worth a look. Try searching for them on google.

Thank you everyone for your suggestions! I'll talk about the ideas with my wife and post pictures back with what we decided to do.

Thanks!