Would love to see more open world content. It doesn't have to be just in the form of NMs however. Why not implement some open world dungeons?

I miss the days of traveling to Castle Oztroja to hunt monsters for magic scrolls and treasure coffers.

Or if you guys have played Guild Wars 2, they had a system that gave rewards to players for exploring hot spots and scenic points. This was a neat idea and rewarded you for exploring!