From what I've seen no one class could truly operate to their full potential without the others without a Titan who would take the front line they are tough and can take some Punch's while warlocks take the second line of defense striking the enemy down in mass number the titans protect them and the hunters sneak and deal mass damage to the enemy through sabotage without the warlocks self rez to revive a raid in its dieing moments or stormtrance for add control we would have a lot more trouble in parts of the raid without hunters shadowshot some boss's would be nigh on impossible to kill without their invisibility grenade we wouldn't be able to get out of a surrounding enemy force without a titans bubble we couldn't use touch of malice effectively on anything but oryx