If my AU campaign ends sometimes (be it because I lack ideas or interest), I might try a mixture of Earth:Final Conflict (the series based on Gene Roddenberry) and the Command & Conquer: Tiberian Sun storyline.
Basically, at the end of the 21st century or the beginning of the 22nd, several major events happen:
o Psionic abilities are proved to exist and can be trained. (Possibly a result of some kind of spontaneous evolution, but maybe not)
o Genetic Engineering produces advanced humanoids (a touch of Genetech)
o The first faster-than-light engine is developed, called Warp Drive (based on theories about spacetime alterations)
o A planet possibly inhabitable by humans is discovered, and first FTL probes are send.
o An alien race, the Taelons, contact Earth. They offer a peaceful relationship, though nobody knows their exact plans.
o Tiberium is discovered
o Terrorist organizations rebell against the Taelons, distrusting their intentions.
o At some time, Earth is invaded and humans have to flee, finding a new home or a way to get Earth back.
Mustrum Ridcully