1) Objective List does not disappear after completing 3, each objective you complete over 3 gives slightly more rewards, maybe +3/5 Esoterics each. Completing all objectives spawns a Gold chest for the party.
2) More varied objectives.
- Put 6-10 lookout points randomly on the map, finding all of them spawns a gold chest (can make it harder by limiting it to one per party member)
- flying races, spawn gold chest for the party with the fastest racer when time expires, spawn another chest for the party with the lowest average time (at least 4 members must complete the race).