That’s exactly my vision with Loodio (https://Loodio.com) that today only has a motion sensor but even that makes a huge difference.

Sensors are also getting cheaper by the minute. For example, I can add a microwave sensor for under a dollar and read hand gestures.

Motion and door sensors tied to lights that come on and adjust with light intensity and time of day is the best automation I've setup. It's so nice to walk into a dark room and have the lights turn on (without blinding you), then turn off when you're gone. Much better than fiddling with dimmers.

you can even group sensors together to have better detection. i love those new presence sensors. it's a lot better than the motion sensors from prev gen.