like it seems the team wanted it to be the grand conclusion to the saga. the covenant are in massive disarray. the flood have been destroyed by a halo activation just outside the Milky Way in the Ark, and lay dormant once more without triggering the rest of the Halo installations. the humans arent at war anymore. Sierra-117 is assumed KIA due to a mishap with the wormhole. Bittersweet but id be fine with that. Humanity rebuilds after part of Earth and the entirety of Reach got glassed. The Arbiter and the Elites return to Sanghelios, now seperate from the Covenant. honestly you could ignore everything 343i made and it wouldnt really matter if you dont like those stories.