I enjoy playing with the HUD completely off because it doesn't obscure enemy movements and animations and makes them feel more threatening because you don't know how much health they have. It really lets you appreciate the work Bungie puts into animations and enemy placements and such. The issue with that though is it also disables your own health bar, your ammo and ability box, waypoints, and all those other very important HUD components. So I think there should be a new option that disables just damage numbers and enemy bars. Go full Halo mode!