Part of being emperor is acting as traffic cop. The game will ship with dozens of playable races, each with particular attributes and abilities. Those of you who just have to have everything your way will be pleased with the race customizer feature. It's too bad that you can't just accept the races that ship with the game, but I guess that's just how you were raised. In any case, you'll need to select the physiology of your race.
Biological races are organic in nature and use existing population to create even more population.
Synthetic races, in contrast, can be constructed in factories. You'll also need to pick a social structure for your race. Human social order is the default standard by which the others are judged. You can opt to pursue a futurist policy of research and scientific investigation or you can pursue the warmonger path and stomp on the silly scientists. Equally refreshing is the de emphasis on cash as a substitute for research.