Going way into hypothetical territory: Do you think they could get Marathon co-op to work on Xbox? Would the terminals be readable unmodified on smaller TVs? I'm thinking they could remove the HUD and use the right 2/3 or so of the screen for the text, and then shrink the illustration to fit into the left 1/3. Dunno about the Final Screens, though.
Also, it'd be cool if they included a controlled selection of third-party maps and scenarios in the rotation. But as far as I know that's crazy and unprecedented; if a console ever tries that, it'll be with something modern and flagshippy.
Finally: A port of Minotaur would be a nice extra, but then again we could be playing Minotaur online now if only someone would start that chapter.
: If they were to release the Marathon Trilogy on XBLA, I would hope the focus
: would be on a lag-free, easy to use online experience (ala Halo 2). I
: would also hope they add some user-friendly option screens for the new
: control setups that would be required (something Doom sadly lacks).
: Last but not least, they could have some sweet "achievements" for
: the Trilogy.