I'm proposing the defensive way of use of siege weapons. So if they want an extra layer of defense - they can sacrifice some culture and population for extra firepower. It could also bring some interesting results for mixed playstyle.
By experience, most of them dont sacrifice culture, nor accept increase their construction time to the roof ( due to extra population population in military buildings) .... but I agree that can bring something new , IF the players decide to use them...which I seriously doubt tho
Maybe some collect players can give their oppinion about that?
At least I would care about culture so much, it matters only for culture victory IMHO
Building that reduces culture but doesn't affect to population would maybe be interesting to see
Making that building to max level would probably mean that player is serious about defence, alho it would reduce amount of passive aggressive players maybe