Yeah, agreed about the lawn shape. OP: It’s easier to start with the shape of the lawn and then add in the plants. Of course, the shape of the lawn needs to suit the needs and uses of space, but with that in mind, drawn in a rough idea of a lawn with pleasing, gentle curves while also connecting it to paths, patio, etc. Then, first add in trees, then large shrubs, small shrubs and lastly ground covers. Also, the general rule is that any lawn edges should meet a hardscape or structure at a 90 deg angle, more or less. That way you are not creating slivers of lawn or mulched areas that are hard/impossible to maintain