I guess the difference in my home is that many rules (expectations?) are unspoken, yet understood.
Politeness and manners are very important to us, and no one has ever had to be told to say "please" or whatever. General respect for each other has pretty much just happened naturally.
Close the door when you use the bathroom. Don't walk around the house naked. These were brought to light when I became a foster parent, and learned that not every family handles this the same way.
Let me know when you are leaving, and where you are going, and when you plan to return, and if you will need a ride home. These are relating to my very independent teens.
No rules or limits regarding screen time or content, because there has never been a problem.
Same with food - I cook dinner; you can choose to eat it or not. There is always fresh fruit, cereal and milk, crackers and cheese, carrots and ranch - a variety of relatively healthy snacks available, unlimited. My control comes in at the market - I simply don't buy soda pop, ice cream, cookies; whatever another family would perhaps need to make rules about, unless it is for an occasion. Then it is generally eaten all in one sitting.
This approach works for "chores" as well. Whoever wants the cleaning task done, simply does it. Or asks for help. Everyone is responsible for their own laundry, but it isn't a matter of rules - if you don't wash your clothes, you will be wearing dirty clothes. This probably started when the Dumplings were around 8 or so. Until then, I did the laundry. but it was up to them to get the clothes into the laundry room.
My kids were mostly unschooled, so rules about studying or homework didn't apply. YoungSon has been in public high school the last 2 years, his choice, but attendance and homework are his responsibility, not mine. He knows he can quit school any time he chooses, but as long as he is enrolled, it is a package deal, with dress codes, homework, arbitrary rules, and all that.
The only current issue that I might make a rule about is who chooses the music when we are driving. The Dumplings disagree on this issue, and it can get fairly nasty on long trips. Sigh...