[Theori]

Demons have been present in the first two eras of E3 and have either completely overwhelmed the rest of the playerbase in numbers or else quickly devolved into a mess of salt and spite when things stopped going entirely their way. I think, so far as antag-by-design races go, the Shadowmire PCs have been the strongest introduced, but please also remember they were revealed during the Academy arc's very beginning, when a good amount of the playerbase were playing children.

I think its more or less an inevitability that the Shadowmire (especially as it becomes more organised) is taking steps to leave this EC state and become more of an actual faction, but I don't think its hit that critical mass where monsters need strong nerfs and get given PC status quite yet.