This might have come up before... but it would be super helpful to see a "location" displayed under usernames in the side user box.
Make it a mandatory field to fill in on sign-up, but just make it an open text box so users who don't want to disclose don't have to. And then those that do could just give region, or city, or whatever they want.
Seems to be a super common question... "where are you located"
Just a thought!