Re seatbelts.
I always have my seatbelt on when in my seat. Most people I see do.
That said, please only use the seatbelt sign when there is good reason to expect turbulence. It seems to me passengers have now got used to ignoring it when they want to use the restrooms. partly I think because I've been on a lot of flights where it has been left on for hours on end with no sign of trouble.
Anyone who flies regularly knows that when the pilot expects turbulence that would actually hurt someone not strapped in, he or she doesn't just put the seatbelt sign on, he or she asks the crew to strap in too. Just how dangerous is the threat of turbulence if it's ok for cabin crew to be handing out scalding hot cups of coffee from unsecured trolleys?
It seems to me that passengers should strap in whenever seated. What's needed is a sign that tells people there is a significant danger from getting up and moving around.