I don’t think there would be a problem with keep up with city maps. They don’t need to create a city with pedestrians, cars and what not. An abandoned ally with a construction yard and what not would fit perfectly well. Games have been doing cities for some time now, I am sure they can do it just as well.
They also don’t need to limit to city, imagine an oil rig out at sea? Huge Titanic like ship out at sea? So many things they can pull.
Hell, even a game mode where the pred needs to escape and FT is hunting in some type of military base, pred is the one doing sabotages and gets his gear back one by one. That would also be awesome if you ask me. The FT should be able to keep spawning as new squads and the pred should be upgraded to be really powerful (some super predator like in the last movie type of thing).