@Tuoni Yeah preperations should definitely be a part of it, i dont know how customizeable towns are going to be, but that could also play out as a very funny aspect.
In regards to siege camps, i would love to see the size of guild play a role, but how it is determined i dont know, that will also give something for the really competitive players to play around. lets say your guild is 25 and a guild of 100 siege you, the number of participants in the siege will then be maybe 40v40? so the smaller guild can either fight it out on their own or hire mercenaries or allies. thus allies should of course also be taken into consideration when the siege is dropped to determine the size of the siege. I would say that the number of participants should be in favor of the defender. so some calculation to determine the size of the fight or maybe it should even be determined by the city size if it is a larger city. as a hamlet would be a smaller fight.