Great idea. i believe that the defencive structures hp can be balanced after the implemention of woe 2.0. Also, woe 2.0 going to lead to forming big guild alliances and their opponent alliances, as one guild cannot supply enough active members for this woe. and to make it supercool, balance should be made so if the castle breaks during woe it would be nearly impossible to regain it at this time. This will bring the true woe spirit of RO. and i think that this castle should give more drops then the usual one, to boost up the competition.
And one more thing: if it is going to be implemented, please make it not only American time zone time. And yes, i think it must be only one castle. So alliances should get members from around the world to protect their precious castle :wink: