That pdf is really helpful. Thanks!
I'm assuming the "Plant X inches apart" indicates how much potential growth there will be?
My ideal scenario is a plant similar to the one in the middle of my first picture, that will continue to grow downhill and cover up more area. Ideally planting fewer plants that will growth farther/bigger than more plants that stay smaller.
Also, part of my motivation is not to put any mulch in the area, since the hill is pretty steep, and right above the pool, I'm worried about the mulch falling into the pool. We currently have that problem with dirt, which I'm hoping more ground cover will solve.