Landscape under pine trees with hill.

Looking for some ideas to make this look better. It’s really difficult to keep grass alive with all of the pine needles and holly leaves that fall, add to that rain washes the soil out and it’s very shaded . Was thinking some big rocks with acidic liking growth and putting some edging around the mulch beds, but not sure what would look good and I haven’t done much landscaping. Any ideas are helpful!