I think there definitely has to be a sugar skull one. In fact, I've been thinking of making the Ringmaster the mexican death cult follower :D It kind of makes sense - he's mildly hispanic looking, there's a theme of skulls and flowers in his room and clothing, and generally this cult is prominent among criminals (drug and protitution rings especially) So once I'm done with the stuff I'm currently working on, I might concept a shrine or at least a painting of Santa Muerte in his room - with a circus-y feel to it, of course.
I'll start building the level on Monday, so no more concepts from me after that time. Might do some extra doodles if I need clarification of some areas (like the stairs)
Sai, would be great if you could do some sketches of the backstage area, I haven't thought much of it :)