Guild war events are great. I would just add some ideas (probably someone already brought them to the forum already) that I believe can enhance the fun we have in these events:
1) At the end of the event keep the guild's list of players win/loose and CP earned until next Guild war. Is quite fun to have an idea of who contributed the most for the guild. Erasing the list right after the event does take some of the fun of retrospect conversation about the war.
2) Between guild war events, why not allow guilds to battle each other for fun. A guild leader or officer could propose a friendly war/match to another guild. If the other guild accept it, then there would be a 1 hour war. We could even have a guild ladder.
3) Allow conversation between opposite guild members during battles. Could be quite fun. The less civilized guilds could still be muted, as it happens in the comments area.