I have to say that the one glaring thing that jumps out at me is the wild variety of hard surfaces, especially the bright white rock that boarders the square seating area in the middle of the yard. The field stone in nice and natural looking and then Bam! that white rock!
To make what you have more cohesive I would recommend replacing the white rock and the scalloped edging with field stone. This will calm everything down - you'll still have three hard materials; concrete, stone and interlocking paver.
The small half round planter kinda things with the Flax also look way too small, that plant gets very large doesn't it?.

Thanks ilikemud. We thought about the contrast in the hard surfaces. This is actually my parent's house and they wanted to recreate a south-of-the-border look. They took a trip to El Salvador and the scalloped edging was in almost every home they took pictures of, so that is probably not something they want to get rid of. The white marble we could do. We could replace it with field stone. Thanks for the idea. Flax does get big, but this is a smaller variety. Also, from that angle, the round area looks small. Here is a better picture of one of the round areas. Also, there are Bougainvillea vines that will climb the shade structure within a couple of years. You could see one of these bougainvillea vines in this photo.

{{gwi:32376}}

What are the bare-wood posts on the bbq pad for? Just curious, not a plus nor a minus to the look.

When you get tired of trying to mow between the scalloped-edged flax, change it to a single long bed and add some more geraniums and daylilies around and in between the flax. That long wall is just begging for a colorful flowering vine or two, maybe pyrostegia venusta or senecio confusus would liven things up.

I agree with ilikemud's comments. I suppose in El Salvador the edging along with the whole tropical scene is quite charming, but in SoCal the El Salvador connotation is lost, and this kind of edging has long been associated with tacky, disorganized, and poorly constructed gardens. My personal choice would be an invisible plastic edge, or a spaded edge.

But the well-constructed ramada, the beckoning hammock, the vivid bougainvillea and geraniums will all serve to transport your visitors south of the border. I would love to see photos again when the plants have attained greater stature.