Could probably change how people enter a scene to accompany a set, to formalize the culture for whether someone is 'in' or not, compared to the whole, 'I'm here but I'm not here because I haven't made a set' thing that I find vaguely ridiculous and awkward.
That's again one of those things that I think becomes much easier in a web-only game. The scene is a web page. You can access it if it's public, or if you've been invited to. You join a scene when you pose into it, and you can do so from any of your alts. The lurking state is still there - it's what you do when you're reading the existing poses on the page to see what's going on. But it's invisible to the other participants.
But alas, telnet.