I think the dev team should look into World Event's on Rift. These were of the same idea that SE tried to accomplish but were actually executed very well for the most part. I thought towards the end of my Rift days, the world events became less spectacular. But after experiencing this event, I came to realize it was what I became accustomed to; awesome events all the time.

Specifically, you should look into the "Waves of Madness" event, a truly epic event.