The "Robo tower defense" bullshit should be solved by giving the defender a certain limited number (based on the size of the settlement) of small unit size militia archer units that literally garrison (think AoE but better represented graphically) towers, and you choose which towers they garrison.
They can be ungarrisoned and moved around like normal units, but they're basically unarmoured peasants and almost useless in combat, so they really make the most sense being garrisoned in tower or along the walls.
Towers should also replenish ammunition.
When the enemy wants to take a garrisoned tower, they should have to break down a fortified door with their weapons and then actually kill the garrisoned unit.
Some towers could have a sally port leading outside of the settlement/castle which can be blocked in a way that is unbreakable, but if a spy is in a settlement, one or two might be opened by the spy, unbeknownst to the defender, allowing for more realistic and tactical (and FUN!) spy/infiltration game mechanics.
Other buildings in the city (doesn't have to be every single building) should also be garrisonable, but more prone to catching on fire than towers.
Battle setup should always be Attacker places his units, then Defender gets to place his units seeing how the Attacker is setup. It just makes sense that the Defender has an opportunity to prepare as the Attacker prepares to assault.
I also think there could be sally battles where the object is just to destroy the attacker's siege equipment or siege works, and then retreating back inside the fort and ending the battle. >>801690
Everything you said about sieges also needs to be implemented.
The fucking gay barriers/supply """rework""" is horrible and basically a mobile game tower defense system. Warhammer fans are literally happy to play Plants vs. Zombies tier game, so long as it has their precious GW Warhammer TM label on it.