By all means keep the minor races in the game. It adds some flavor, and ways to generate income without giving away strategic technologies to major opponents. They can also serve as nice buffers against aggressive majors, if you supply them with enough goodies.
Changing races from minor to major (and vice versa) based on yearly power rankings does not sound like a good idea... It might work, but it destroys the story line... And think of what it would do to the zones of influence in the game. Would you like your major neighbour, that you have been attacking and conquering, suddenly switch over to be a minor that can be attacked without penalties by all other hungry neighbours?
As suggested earlier, some limitations would need to apply to minors, maybe even with some storyline behind it (I liked the concepts in posts #24 and #25). Some limitations that seem sensible to me:
-1) A cap on number of planets colonized (depending on map size), or on number of sectors with planets, to limit the expansion to the close-to-home sectors. Maybe even NO expansion on the smallest map sizes.
-2) somehow limit the minors to non-aggressive technology... Hard to detail how... Maybe a bonus on defensive properties, and a penalty to aggressive effects... A warship would have double the defensive capabilities but only half the offensive ones.
-3) If new minors enter the game at some point, they did have (in GC1) all available technology up to that point, but were so weak / defenseless that it made sense to always gobble them up... That should not be the case in GC2, if possible. Either less tech, or appear with some kind of defense, but non-aggressive !
-4) do not allow minors to initiate trade
-5) do not allow minors to research galactic achievements... They give them away quite cheaply IMO when I trade with them in GC1...
-6) give minors penalties the further away from their capital that they get (either in range or in numbers beyond 1 planet). A bit similar to #1, and maybe harder to implement.
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