I think it would be a great addition if you could stay 'out of the spotlights' when you log on. Either to work on your avi or to talk with friends, without others being able to approach you in chat or by invites. So, besides the red, yellow and gree, maybe they could add purple or pink to signify "I'm busy"...
Oh well I guess a option to only chat with the ones you know would be good but then how would I have met you sweetie? (Detsamma sötnos, puss på läpparna och där nere )