The beauty of Halo was/is that the combat is a means unto itself. It isn't an RPG so there's no grinding, only the pure struggle and bliss of open-ended combat. As excellent as the gunplay in Destiny is it is a means towards a different end, one that is not guaranteed: in Halo when my enemy falls I am done with him, I have vanquished a unique beast but in Destiny there is only the promise of maybe getting new gear or materials. RNG sucks so hard gentlemen.