I don't think Erfworld brings much to the table. There was so much BAMF anime before, and bamfing into the middle of a brutal conquest is no news either. The only thing it can teach anime creators is not use ancient Japan as the world, but try the contrived game world... oh, wait. Digimon.
Face it: Erfworld's design is a worse foundation than the curse of a drowned individual. There's no consistency in it at all. You want another Druaga, only worse? Spare me.
Wanda's boobs are great, but anime world has plenty of that already, plus better foundation. And when it's not better, the result invariably sucks.