I realise that some people will hate this idea which is why I'm merely suggesting it as a fun event similar to the no downed state week. Quite simple really as the title suggests. Just remove all doors from the maps and make it so that no siege can be placed for the duration of 1 reset. I would also suggest that all mortars and canons be removed too. Having a nice buff to magic find, WXP and reward track to accompany it would also be good.
Why? Well, aside from some fun fights on reset night and the occasional roaming skirmishes during the week, there can sometimes be a little too much siege camping in t3 towers. This might encourage more fights over objectives (or it might make people go do Istan farm instead. I don't know.) But it would at least shake things up a bit.
I mean, some of the most regular ongoing skirmishes happen in and out of a cheese walled SM... Sieged up towers stop players from interacting altogether because no one wants to deal with that mess. What do you guys think?