Most events in the open world go untouched.
I propose that each event should award some type of medal when completed. These medals can be used to buy rare materials, ascended weapons and armor, and other items.
The objective is to encourage players to complete a wide variety of events throughout the world. The prevent players from cycling the same events over and over, each unique event gives out medals on a daily rotation. The number of medals awarded by each event scales depending on the popularity of the event. Popular and easy events give 1 medal. Unpopular events that rarely succeed or finish give up to 5 medals.
Rewards are character-based. Completing the same event within 1 minutes on the same character, however, will not award medals.