Grass is low maintenance compared to keeping weeds out of a hillside covered in shrubs.

I once saw a lawn on a slope in Italy that was essentially formed as a series of ramps in zig-zag up the hill, completely mowable. There were some parts with low retaining walls, but not much.

One wonders what sort of equipment is used to mow the steep hillsides of Forest Lawn Memorial Park in Glendale? Anyone know? Maybe it's a question of splurging on the right equipment, or paying for a monthly service.

I'd consider my budget against every possible option before digging up the hill to plant a garden that will have its own maintenance issues.

There is no such thing as a no/low maintenance garden. Do you really want to play mountain goat with creaking joints in future years pulling weeds and trimming back some type of ground cover plant that you were told never needs weeding or attention? Life in the gardening world is not perfect. And, take it from one who knows, the older you get the faster the weeds grow! Two suggestions:
1. Often it is possible to mow steep slopes by purchasing the widest mowing deck that will fit your riding mower model. The extra width helps to stabilize and hold the mower when mowing across a slope.

2. Advancing years mean that one must make choices which allow remaining in the present home in safety and without the stress of leaf raking and cutting grass. Hire a mow and blow company to care for the slope. You will probably realize in time that this is the one expenditure over the upcoming years which will allow you to enjoy your lovely home for many years.

I agree with the prior posters that weeds in a groundcover bed cannot be underestimated. If weeds are allowed at all, they will take over and destroy any possibility of a nice looking bed. On the other hand, I think that developing weed-free groundcover beds is possible. It requires that one be especially vigilant during the first two years. The rule of thumb will be 'never let any weed produce seed; it starts the whole weed-removal cycle over again. Creating a manageable groundcover bed also requires that one make a concerted effort to eradicate weeds BEFORE installing the groundcover plants. Otherwise, there will be too many weeds to combat and they'll win the battle. If you have an aversion to using herbicide as one of the weapons in your arsenal against weeds, I'd also say forget about groundcover. Hand pulling alone wouldn't get the job done. Another factor is temperament. What some people do easily, others may find difficult to accomplish. Before jumping whole hog into creating a large groundcover bed, I'd suggest give it a try on a smaller area--100 to 200 square feet--and see what you think. If it's for you, you'll have some experience and the confidence to expand. Begin by killing weeds and mulching an area. Just keep the weeds out for the rest of the summer. Meanwhile, you could root some groundcover cuttings in a scaled down "nursery" for transplant later in the summer or fall. It's pretty much impossible to spray herbicide in areas of any size unless one has a back-pack spray. I fit mine with a fan tip spray head so it's much easier to spray with precision. A round tip (what all the sprayers come with) is not near as good for spraying herbicide where you might need to get close to "good" plants. At a prior home, I developed and maintained about a quarter acre of English Ivy and I found it to be the easiest patch of ground to take care of. I only had to edge some of it once or twice a summer and spot-spray herbicide on any rogue weeds that sprouted in the middle of it. Once the groundcover matures, a little herbicide sprayed here and there to get the rogue weeds will not be noticed. (An infestation would be a different story.)