%100 agree with your points and i want to add some more;
Some cities and castles does have different layouts but not different enough use different approaches.
I think destruction right now is decent enough. What find lacking is the siege layout varieties. I think our engineering skill should drasticly change the equipments lay on the siege. for an example worst quality battering rams or tower, maybe even they should be acquired with a perk or something. barricades have much lower health or less barricades. If you have better engineering skill you should have more arrow barrels, reinforced barricades, battering rams or towers. this way you can choose your most preffered tactics through perks you choose.
In history, castles and towns usually build on top of hills and shorelines. I dont see that in bannerlord. Some cities can be in so difficult terrain maybe towers shouldnt even be an option to siege them.