Yes, that works also, since Catholicism is so broad, and the Mechanists were a deluded off-shoot of The Hammers. One of the early missions in Metal Age was robbing some warehouses near the sea front which began with an eavesdrop on an argument between Hammer and Mechanist. That kind of oppression is something that could be expanded upon.

I don't know what The Freemasons represent, or how submissive or subservient they might be to the Catholic Church, but I can imagine the negotiations and/or compromises between the elders of the various factions that could go on behind closed doors in the game, which is what I'd like to hear (and/or create) more of.