Sieges are currently broken; I think pretty much everyone is aware of it. From being allowed to log in, as an attacker, inside the enemy's town, to being able to teleport through walls to the flag having virtually no health, the issues plaguing this core mechanic of the game are numerous.
-Any attacker who logs in the besieged town, during a siege, should be automatically teleported to the attacker's siege camp or simply spawn there.
-Any and all teleport spells should be blocked by walls and palisades.
-Defenders should have to manually open a gate to go through it (like we open doors in buildings) and gates should automatically close within 15-20 seconds of being opened.
-Flags should have magical and physical armor and tremendously more health.
-The Attackers' Siege Camp should have a bubble around it so defenders cannot pull a reverse "log in catch" and log back in right on top of it. If they try logging in within that bubble, they should be teleported back to their flag.
-Until fixes are implemented, the Conquest mode should be temporarily disabled. I know we are in beta but the goal is to retain players, not see them driven away because they can lose, in a matter of seconds, what they have worked on and accumulated over weeks.
Conquest Mode Revamp:
The Conquest mode should be revamped. My proposal is to make it more interesting by introducing time constraints for the Conquerors on what they can do.
-Constructing new buildings.
I propose a three-day moratorium on any and all destruction (besides fields). First, this will prevent the near-instant deletion of the town's bank and its housing. Second, it'll actually give time to the conquered to plan a counter-attack, rally their friends or, perhaps, abandon the city after taking back their belongings. Taking back their belongings force them to enter a now-hostile town and escape with a lot of stuff on them. It creates opportunities for the conqueror and the conquered by rewarding patience for the former and guile for the latter. It creates OW-PvP scenarios where one might kill an enemy who has A LOT of stuff on them.
It also delays Stone Aging and gives a chance to the Conquered to fight another day, if not immediately. It brings more layers to a rather simple, blunt system.
Lastly, I believe that when the destruction of a recently captured town is enabled, it should be within time constraints. In my opinion, it makes no sense whatsoever that massive buildings can be destroyed in one click and a whole town be razed to the ground in 10 minutes. It's not only nonsensical but it is sincerely detrimental to the longevity of the game. I believe that once destruction is enabled and the Conqueror decides to start destroying buildings, they should be put on "destruction timers": the more complex/important the building, the longer it'd take. A 2x2 house, for example, could take only 12 hours whereas a townhall would most assuredly take a full week. The Conqueror could initiate destruction of all buildings at once, but they'd be set to different timers and thus prolong the window of opportunity for the conquered people to recapture their old hometown.
This, in turn, would also make it so if they do manage to recapture it, the town wouldn't be a wasteland but would likely retain most of its important buildings.