Grass is a marvelous plant, but that doesn't mean it has to be used everywhere. Some situations require large expanses of lawn such as areas that could be used for recreation or pets. Nothing else quite fills the bill like a soft green lawn to walk or run across, and while a pet may seem to prefer to relieve themselves on that favorite spot behind a certain chair, most dogs prefer the outdoors on the lawn.
For areas that don't require this large expanse, or for areas that receive little foot traffic, then you can reduce the turf areas by including different ground covers, gently curving planting beds that weave around the property. Once established these landscaped areas require less maintenance, watering and supplemental fertilizers. What you don't want to have are areas that become bare soil during part of the year. Healthy lawns, even when they're dormant, still have a root structure and an above ground biomass that keeps the soil in place and prevents erosion. It is soil erosion that is a major cause of water polution. So make sure when considering different options to replace a lawn, that you're not making a situation worse just to replace grass.
Often less is more. Less lawn square footage, actually heightens the impact of what lawn is visible. Imagine a property that has nothing but an expanse of lawn from one edge of the property to the other. Not exactly a pretty picture. Now cut that lawn by 1/2 and introduce various perennial gardens that don't require buying large flats of annuals every spring.
Developing a comprehensive plan for your property is a great way to get started. Perhaps a landscape architect can develop a plan that you can implement over several years without costing a small fortune.
The important point is to think outside green box. Even if you don't know the difference between a Japanese Maple and Japanese Yew, you can do things differently.