I love it! If I'd seen this idea/article a couple of years ago I would have seriously done this in our yard but we are selling this house and moving 100 miles south to our retirement home next summer so I don't plan on any major planting/landscaping chores here. Our backyard slopes down to a waterway and before the riding mower died for good it really scared me to mow that slope so I'd leave it for my husband. When we adopted a dog a couple of years ago, my husband installed a fence so I had no more worries about the mower getting away from me and going into the water. I now use the self propelled walk behind mower to go down the slope and he uses the weed whacker on the other side of the fence along the waters edge.
LOL, after seeing your lovely photos I'm going to be thinking of someplace at our new home to build a slope/ berm just for daylilies!