I was snowed in for the last couple days, and spent a good chunk of the time playing H2A and H3 back to back. Looking at the story as a whole, the new terminals add an interesting wrinkle in that ONI had been observing and tracking Thel 'Vadamee for years. They knew that he was the single most deadly and destructive shipmaster at the Covenant's disposal, and tried many times to take him out.

This makes me wonder whether anybody knew that the Arbiter who offered his allegiance to humanity at the end of the war was the same guy. At the beginning of Halo 3, the Arbiter seems to have full run of Crow's Nest. Other than some funny looks from marines, he's trusted completely, even though this is one of the UNSC's last secure bastions on Covenant-occupied Earth. So did Cmdr. Keyes et al. know the Arbiter was Thel 'Vadamee, Destroyer of Worlds, and just not care? Maybe only a handful of ONI operatives made the connection, and opted not to share? Maybe the Arbiter's real name never came up.

Hood's choice of words at the end of H3 is interesting: "I remember how this war started, what your kind did to mine." He says "your kind", not "you", thus avoiding placing blame specifically on the Arbiter. Perhaps he was being tactful, or perhaps he was/is truly unaware that this particular Elite was responsible for more human deaths than any other.

Basically, I'm still hoping all these years later that we'll be told the story of Arbiter, Keyes, and Johnson returning to Earth after H2. That must have been a spectacularly, fascinatingly awkward moment.