I had this idea. What if, when we finish CEA, we will get an extra mission (just like in Reach) after the credits and that thing with Johnson. In this mission we will get to fly the longsword and fight enemy banshees in a space battle. It should be beautiful, flying with Halo in your background, fighting some remaining covenant forces while Halo gets destroyed behind you. As long as this doesn’t have canon issues of course. It should be short though, like fifteen minutes, and should run entirely on the Reach engine.
TLDR- A longsword space combat extra mission will be fun.