I think I'm a fun flatmate. I'm always cheerful. I go on tour with my band so it's 12 people on one bus and I feel like I'm the one who's happy in the morning. I'm not a chaotic person, but I might slack off on doing the dishes from time to time.
Look at the Coen brothers. All their minor characters are as interesting as their protagonists. If the smaller characters are well-written, the whole world of the film becomes enriched. It's not the size of the thing, but the detail.