In the Grimoire you are constantly hearing about these battles of years ago (Twilight Gap for one). I personally would like an event ,similar to the Iron Banner and Queen's Wrath, where around 10 players could fight a huge mission ,not raid proportions but more like a longer story mission. When a Guardian falls a set amount of times they would be returned to orbit where they can restart the battle. This could create new exotic bounty for a weapon since Gjallarhorn was forged after Twilight Gap. This should be included in a free update so for better gameplay experience(added). Please comment with your ideas.