Destiny needs to use vehicular combat. There is like one strike with vehicular combat and I have never used a vehicle in the crucible. Is there even vehicles in the control mode? One of the best ways you could cooperate in the Halo campaign was to have one guy driving a warthog and another one shooting. In destiny there is no real working together in the campaign in the same dependant way. And flying vehicles, mix up the shooting with flying and other vehicles. Fun enemy vehicles that are not just bulletsponges. The old scarab had to be climed and blown up from the inside. A bossfight that couldn't be killed with an auto rifle. Ground and air fights at the same time makes for more cooperation when you need one guardian to take care of the enemies fireing from above. Also why are there no friendly npcs? Is that something bungie has said they dont want to use? Because they create yet another interesting way of taking the focus from just shooting. It gives the player the ability to save people by moving quickly and skillfully. Another interesting mechanic would be to let people help you in story missions. Lets say there is an epic battle in the campaign, why not bring in reinforcement as guardians in dropships or droppods. You could use the dark souls way of having people sign up for droptrooper service in the tower and giving them the option to help someone in a story mission with a prompt. Like a covenant ring from dark souls. I use to love when I got reinforcement in halo. Makes it feel more alive, like you are not fighting alone.