Fridge Brilliance - Near the end of the series Elijah discovers that their universe is actually two dimensional at its foundation, and their perceived third dimension is a sort of unreal hologram or projection. Which is precisely true: at its base Planetary is two dimensional images printed on paper, and their perceived existence only takes place when the reader projects them into his or her mind.
Related Fridge Horror: Unfortunately, the holographic principle in Real Life quantum physics states exactly the same about our own universe: there is no way to distinguish a portion of 3D space from an hologram projected on his confines. We could all be in a comic,or a movie, and we would not realize it anymore than the characters of Planetary do.
More Fridge Brilliance - in issue 8, almost all the storylines mentioned by the deconstructed Superman analogue are stories that were actually printed in the Dark Age, and happened to either Superman or Miracleman.
Further Fridge Brilliance: Jakita, the only woman among the main characters, is presented as pure sex in a leather catsuit, right? But read the comic carefully and note she never shows even the tiniest bit skin beyond a rather modest decoupage, and is never suggested to have the slightest sexual or romantic interest in another person besides Jack Carter, with whom she doesn't exactly spend a lot of time. There's a huge subversion of the whole Love Interest/ Sex Object paradigm going on right under our noses.