Bungie needs to get out of its rut.
Bungie has always been in a rut. Halo is not, in the end, much more than a very very polished retelling of Marathon. The company is really a one-trick pony.
The gameplay and design are very different from Marathon, and the narrative ambition on display clearly taps into the likes of Iain Banks. The similarities are more out of a desire to create a kind of overall mythos, so that we can feel some of the same horror the Wrkcntater evoked when we encounter the Flood.
And, in any case, Oni and Myth were both solid (or, in Myth's case, excellent) games of a very different breed, proving they can do other things well.
In fact, on that note, Pathways into Darkness was a fantastic and often overlooked game with a lot of really original design choices. The fact that Halo is their smash hit franchise shouldn't disguise their versatility.
Bungie is no more a one-trick pony than Volition was, and the two studios share a lot of remarkable similarities (including their tendency to produce derivative but highly polished and enjoyable work.)
