Something that will make games as a whole realize that an educational game need not necessarily be limited to Sid Meier, Will Wright, and edutainment. A proper work of literature would be wonderful, not just a novel made into a game, but something written for this medium that's more than just the loose shell of a backstory Halo provides. Something that will keep the mainstream occupied, but at the same time not make the underlying story not so underlying, and not so damned ignorable.
The HL series was great and all, but the amazing writing and presentation the games have is often overlooked.