Secret Societies has me thinking. Existing fantasy/scifi 4x are primarily hard fantasy (i.e. DnD/Tolkein esque) or alien world/space exploration scifi. In their scenarios/game modes, Civ is touching on more of the less well represented sci/fantasy subgenres in gaming. 'Our world with fantastical elements' so to speak. Vampires, Cthulu, post-apocalyptic, Steampunk (Civ 5 Empires of the Smoky skies scenario). I doubt there's a market for full versions of a 4x of these, but it does seem like the game modes could be expanded as more significant game modes to purchase or stand alone $30 spinoff styles. I'm curious what people are mostly interested in. My categorizations are pretty vague, let me know what I forgot.