This depends on how many people are around and where the sun is. I love having the blinds in my home open, but I don't want people staring into my home, nor do I want to be blinded by the sun. I usually have them partially closed in the afternoon as the sun comes right in the windows.
I have double blinds in my bedroom so in the day you can see through them but no one can see in.
However, as per one of my questions, one night i forgot to close the heavy blinds!
I get natural light with this system, and in the other areas where no one can look in, I have single blinds which are great as I open them to let the sun in in winter, and leave closed to keep the heat out in summer.
Never the 3 bedroom curtains, but sometimes the middle 1 of 3 of the living room ones.The people 3 doors down can see in, if we leave them open, as there house is on higher block than we are, even though our house is like a 2 story except it’s not!,
Open. I simply cannot stand rooms being dark, it feels like a morgue! Himself's mother never opened her curtains and it was just awful. Even in the nursing home she will fight to close the curtains . . . sad, as the view is very nice from her window.