Chances are, once I've completed Destiny's main story campaign, I'll want to play it again... likely with my Level 20 character. This won't be as much fun if the enemies I'm facing in the prologue mission are still Level 1. In the Beta, you could only crank up the difficulty to 3 levels higher than the default difficulty. So, my message to you (Bungie) is this; if the game doesn't already have a Level 20 Difficulty setting for all the Story Missions (including the Prologue), then please try to patch it in post-launch via Title Update.