While the idea is awesome, hence why t was fun in ffxi, this would actually fix problems, and cause problems. By making this on all 3 nations people may take part, but again they'd probably gnore limsa and grid a fair bit.
The problem with Beseiged mainly was that the rewards were limited, Seals would be appropriate to fix this, the second was the OP attacks killing you from mobs you can;t see. From what Yoshi has said about the engine it might, might just eb able to handle this type of fight correctly. And with dynamic lowering of system specs to render even more models on screen it may be actually a very very good event.
