My thought is, what happens when the minor civ is uplifted mid game? Do they suddenly get a bunch of planets to so they can compete with the established civilizations? If a minor civilization is uplifted without proper resources, it would be easy prey for the other civilizations.
If a minor civ is uplifted mid game, but it has no means to do anything, did anything change?
i would think that uplifting a minor race would require an active element from a player or other major race
for example you would need to make donations of research points to help that race reach a similar tech level as the rest of the galaxy and protect it during its infancy (the uplifting stage) once it becomes active as a race it would most likely see you as a strong ally due to the help you provided it
however there is a chance that the tech you helped the race with blew up in their faces making them hate you for all eternity....
on top of that if a minor race has a small chance of getting a random super ability (mega researcher, super ship builder, etc etc) its possible that such a race could become a real powerhouse later on in the game even with only a few planets at the beginning