I'd like to suggest that this be done collaboratively, having either the winner pick the next style/subject or a user generated list from which the next style/subject is picked randomly.

Something like a style choice and the. 2-3 subject choices.  So you might be Art-Nouveau Skulls/Bears/Alien or it might be New School Fantasy/Beach/Animals or Chiaroscuro Cyber Punk/Metal Band/Christmas.  You could also use visual cues to help explain visually rather than through text.

I'd also like to suggest voting done only through participants.