Landscape drainage

Large 2-acre lot with significant steep slope. When it rains water runs from one side of backyard to other in an area between a steep slope and the hard scape poured concrete patio. From there it runs down the side yard to the front yard where another steep slope has it run to street. In the process all mulch, grass cuttings, dirt, leaves, and other debris is washed away and deposits in front yard before water get to the street. Considering some sort of waterfall incorporated into steep slope in backyard as a water feature. All landscaping must be very low maintenance. Looking at groundcover over extensive mulch. Yard needs to be better graded as there are high and low spots. Lots of small rocks as well as some very large rocks/boulders. Most house down spots sent underground to popup drains in yard. Some just stop near foundation on driveway, sidewalk, patio or just to lawn that need to be sent underground and away from house. No down spots are sent to curb cutouts at street. Backyard and side yard have some French drain work but it is not very effective.