Hey all, my first post, so be gentle:

Anyway, let's say the following happened:

The Sa-Matra is defeated and both subspecies of Ur-Quan are thrown into chaos.  This allows the combined fleets of the Earthlings, Syreen, Yehat/Pkunk, Chmmr, Shofixti, Arilou, Orz, ZFP, Utwig and Supox to win a string of victories against the Ur-Quan.

The weakened fleets of the Kzer-za/Kohr-Ah begin a mass exodus in the direction where the Kohr-Ah originated ('east'), because there are no races left in that path to get in their way.

Their resources depleted, the allied races are unable to pursue the fleeing Ur-Quan to deal them a crushing defeat, and instead turn inward to reconstruction.  Years of peace and relative quiet in the galaxy ensue.

As spheres of influence expand, disputes over territory begin to occur more and more frequently.   The new alliance becomes entangled in a web of secret treaties, economic arrangements, political mechinations.  Leaders grasping for power become jealous of the clout of the captain, and volunteer him to lead an expedition to liberate worlds enslaved by the Ur-Quan.  Jaded by the highly political nature of the New Alliance, the captain is all too happy to leave.

Anyway, that's the setup.  Then various things can happen like there are people on the mission that have covert agendas, some of the races that are freed aren't very friendly, some races have moved in during the Ur-Quan's absence and don't appreciate old races reclaiming their territory, there are still some Ur-Quan battle thralls that were left behind to guard the sector, etc..