The main use I've found for the book is helping to flesh out the storyline of SMAC. I'm always a sucker for the storylines of games, and SMAC was the first (if only) 4x strategy game I've found with an interesting story. After playing the game, I tried to devour all the fiction I could find (and at that time, all I could find were the short stories posted online - I still haven't read any of the novels or the graphic novel). When I saw this sourcebook at a Sci-Fi Convention, I HAD to buy it. I created countless new factions that I thought fit in with the world as presented in the game (and later the GURPS sourcebook). A Humanist faction that could almost be considered a direct counter in ideology to the Cult of Planet ("Yeah yeah, Planet's great, but MAN is like a fledgling GOD!!") An Empath faction made up of rouge psychics (Like the Datajacks were rouge Probe Teams and hackers) meant to be a sort of compromise between the spiritualism of the Gaians and the mercenary lifestyle of the Datajacks. A faction of Progenitor whorshipers (best in games where the Progenitors themselves didn't appear) who were again like the Cult of Planet, but whorshiped not Planet, but the race who CREATED it.
The point I'm trying (and probably failing) to make here is: keep in mind your storyline. I think MOST of the people who are interested in this mod are interested for the fictional world it takes place in. So DEFINITELY don't scrimp too much on the story. Of course, make the game BALANCED and PLAYABLE. A bad game with a good story is still a bad game (though I have been known to play such games at least one time through - anyone else ever play Terror Trax?).
BUT, your storyline will help provide a focus to the games direction. Plus, when you flesh out your storyline, it can provide you with clues as to how you can extend your existing ideas (like my faction ideas above came from knowing a little more about the storyline).
As I understand it, your mod is attempting to keep the "world" of Alpha Centauri in a basic sense, but expanding it out to encompass some new ideas as well (and to work with the game mechanics as they are/will be). In this sense, the GURPS sourcebook would probably be of help. It is for a table-top RPG so the focus shifts from the global view of the PC game towards the individuals living in that world, which I've found VERY interesting and useful.
Darn it, I'm rambling on again. I'm done... I think... for now....
