A juniper like (blue rug Juniper) is more suited to your landscape than a Clematis in my opinion. They are low maintenance and if mass planted will cascade down the slope. They are extremely low maintenance. They will look nice only if maintained without any weeds popping in the bed. So some weeding will be necessary until they are established.

Thank you both for the suggestions. It does seem like a very logical choice.

I think that I would go with the grass theme and turn it into a flowering meadow look. Right now you appear to have some Rudbeckia/black-eyed-Susan growing there. I would add some additional flowers of similar style (there is currently a thread on the perennials forum about flowers that grow well in grass) to the BES that will grow with the grass and have many roots to hold the soil. Not all the suggestions on the linked thread will be happy with the dryness of your slope, but some will be.

To my mind, the problem with the juniper is that you can't keep mulch on that steep a slope while the juniper is getting established, and bare soil will just erode. Even once established, it will be years, if ever, that the juniper will have dense enough roots to replace the soil-holding capacity of grasses on that slope. And grass or weeds poking up through juniper looks awful.

There are some vines that might work there with the grasses such as Virginia creeper, Parthenocissus quinquefolia (lovely deep crimson autumn color) or its relative, Boston ivy, P. tricuspidata.

Alternatively, and more expensively, put in a ~3' wall which will need some engineering and a competent mason to do. That will give you a still sloped but not so steep bed that will hold a bit more moisture, retain mulch, and have less likelihood of severe erosion.

Mass planting of blue rug juniper will do it. I have a similar slope area in my property and when mass planted (1 plant every sq. ft) did the trick. It got established in just one year. You don't have to buy the very large specimens to accomplish this. Just buy the plants in the 1 quart containers. I waited until the end of the season when plants were offered at 70% discount at Lowes & Home depot. I picked up about 50 plants from multiple stores.

Alluvaboy, the difference in our experience may reflect differing soils. Mine is a fine sandy loam that has required a densely rooted groundcover (like the grasses in the original photo) to hold on a slope less steep than My Name's.