I’m trialling Flyzoo chat… it uses buddy press logins as username and users can upload avatars, and they have told me that within a week they should have update to restrict guests, so chat does not show up on front page unless user logged on. Its hosted on the cloud, so no load on your host..It is not free but for what you gets its cheap..starts at 1.90 per month. I’m new to WordPress, but it seems good. Support responds really fast which is always a bonus..
Hope that helps.. http://www.flyzoo.co/
