I've had some ideas for The Exodus as well over the development of Cam 4.
We could have it be something of a Gauntlet like Cam 4 is, but they also need to sometimes go "out of the way" to grab technologies that are needed. Not quite so hardcore as Cam 4's gauntlet is though. It's a LONG journey so I'm sure some interesting things can be thrown at the player. I could draw up some prototype maps and explore the possibilities.

