Sounds more like a guild tournament than a wars.
Not exactly sure what you are asking, but if you just looking for opinions, here is mine.
Seems like an okey content to have in a game, if you can automate it all.
And for something like this, you need to ensure balanced META (most efficient tactic available).
Otherwise you will end up with crowding, or just stack of OP classes.
Win condition of destroying damage pole, seems very unimaginative of better ways to let guilds battle, as damage is the only key factor, not much tactics involved