Really good. I agree with it all. Some have happened naturally for us (saying please and thank you, good conversations) but some definitely need work (napkins and holding forks etc correctly).
I wholeheartedly agree with teaching them the correct way of dealing with food they don't like. It's awful for the host to be faced with 'ew I don't like that' when they've been told the child eats anything. When my eldest is out at friends he's expected to eat everything he has on his plate or if the food is in dishes to be got themselves, to polity decline an item.