Always kind of hoped that they would do a remake of the trilogy from the perspective of Cortana (as a bridge to Halo 4). The Halo Legends Origin gave me that idea. i.e. why not have her contemplate things, reviewing the events of H1-3?
In that sense, it is established that there are bound to be inaccuracies in her recollection, and that would give 343i freedom to update the trilogy (i.e. different looking everything), armour abilities (e.g. sprinting >_>)... things like that. Experiment. Get feedback, make Halo 4 better. *cough*
Heck, they could have cortana say a few different things in co-op as she hallucinates multiple chiefs.
Guess that'd be quite the undertaking, but I was thinking it'd be a condensed version of the 3 games based off of what she was present to record & whatever John had reported (or maybe introduce the idea that she can snoop his brain for memories. e.g. skip arbiter play, but have her fill in the blanks.
Basically a trilogy re-imagination through the eyes of Cortana. Halo: Cortana Chronicles or something.
Crazy idea, I know.