Skyrim did something right with its open world exploration. Unique story type missions could be linked into the open world and could have replay value. Aside from the marks, nobody replays the standard story missions much it seems. Really, I would have also done the whole plaguelands/Iron Temple area as a continuous, continuous, and living open-world. Destiny feels so cut off and dead-ended its not funny. Really, how cool would it be if a door somewhere in Venus opened up to a dungeon-like area to explore with some story or puzzle-solving elements or you can return to previously closed-off strike-site for a random solo-friendly boss spawn or other type of encounter on a patrol? also, why not have vendors and bounties available in patrols too? A mix of social and actions spaces is a cool thing.