Yep, these are the kind of open world battles that SE should be pushing towards, which is why I wonder why there is so much resistances to the multi-claim system SE is developing. The only way you can have this kind of large-scale content is if its open to everyone on the server free of LS or party/grouping restrictions.

That Guild Wars clip looks like it builds on what Warhammer introduced with the Public Quest system, where everyone gets to contribute to the fight in their own way and is also rewarded based on their contributions. Would definitely be cool to have fights like that in XIV of that size and scope but honestly any hope of that seems so far away.....