I would argue that the core pillars of gameplay are the guns and abilities. I think everything that has been added as far as activities go has been at worst fine, and mostly good to great. My issue is that we are supposed to be "celebrating our triumphs" at a time when your character(s) feel less powerful than it/they ever have. I understand that a lot of the changes were made to temper power creep, but artificially trying to increase difficulty and promote diversity this way alienates a player base conditioned to play however they want. I imagine that Bungie thinks that allowing everything to be OP, will cause the game to become to stale, and a challenge is needed to continue to draw interest. Maybe so, but taking away a players ability to be functional with weapons/armor/classes that they enjoy playing will do the same, in a much faster and more violent way, hence all of the whining when a large patch/change is made.