1. The drop rates are terrible. 2. Legendaries can be given from the End Roll. 3. Blues from the end roll = Cryptarch XP. 4, Cryptarch XP has a better chance of a legendary. 5. Why waste time on enemies that don't matter? 6. Faster runs mean more you can do in an hour, so more Vanguard XP. 7. All of that combined makes doing a quick strike run better than a long and drawn out one since you will have to do the strike multiple times since the game lacks substance and only has a handful of unique activities.