Maybe it's just me but I think these last couple of ideas you posted (the nation parallels included) actually make too much sense to be "weird or unusual headcanons".
Heck! It wouldn't surprise me if they end up matching the canon, either partially or entirely.
My only weird, non joke headcanons are that Eliza owns a art collection depicting her in several styles, ranging from her pre-parasite days to current times and covering the Skullverse equivalents of ancient Egyptian art, Van Gogh, William Blake, Picasso, Rodin, Rembrandt, etc. and that she has a collection of skull cups made of her most distinguished enemies (Delilah's being her most prized possession), all lacquered and covered in gold leaf.
(PROTIP: I'm not really good at these things... -_-" )