Less-is-more landscape approach - with a gravel mulch you have an attractive background while the (undisturbed) plants have room to spread. Helichotrichon, sedum, thyme, with pebbles, large and small rocks. This is very well done.
Can snake plants grow outdoors without planters? As an added bonus the snake plants (AKA Sansevieria trifasciata) are one of the better plants at filtering out formaldehyde, which is found in many household products.