The smiling registered user icon might seem like a random idea but it isn't. Reason we decided to go with a more uplifting face is to help make WP a friendlier environment (yes small, but still a step towards somewhere). We want people to assume good faith on other users' actions but that is alot of times harder than it sounds. When someone makes an edit that you might disagree with and when you make an effort to find out who this user is, you are greeted first with a smiley and then a name, reminding you this is a person of emotion, be nice!
I don't know where I stand on whether it's confusing or not, and that's because I don't know how users are reacting towards them.
The flag icon with sad face, I wasn't aware that we were using that as a final icon. I will have to speak with Pau first to see his thoughts on them. My hunch is that he used it as a placeholder. We have a flag icon used on Flow that should be used everywhere else flag action is needed.
mm