You could create levels or tiers of different flowering plants or shrubs. If you consider what time of year each plant were in bloom it is possible to make a hill of color for the entire growing season. With a few calls to a local garden center you can come up with a virtually maintance free spot of beauty.
Building a dry creek bed first is a good idea. This will help with soil erosion. Juniper plants are also a good idea. They also help with erosion. If you use these plants you won't have to worry about cutting a steep hillside.
Depending on your locale, you have great options- consider groundcovers like English Ivy, periwinkle, low juniper. If wooded consider a garden option like daylilies and judicious rock placement.
I find waterfalls and small river like designs are fun to do and enjoy for a lifetime. also it can increase your property value. if your looking for cheap and less maintenance ice plants can also be a well choice. Grass and bushes also can be a good idea but can also cost a lot to maintain.
Terracing the hill could be a beautiful addition to your lawn and home. Using either wall builders or landscape timbers would add lots to you updating your lawn.
