Quiescence might work, but I'm not sure if I would go with that over Repose. Definitely not Popular though. Popular assumes the majority is excited about something unusual, whereas social could mean that it is nice but more expected than unusual. Social also implies that there is a gathering of people, whereas popular could mean something that is done by each individual on their own. ie: a popular dress as opposed to a social banquet. Ultimately it is up to you as you are putting the whole thing together, and that could just be me holding on to my own thoughts, so go with what you like most.