I'd also personally prefer getting the scale correct, or at least more-or-less correct.
Doesn't need to be exactly right, but the point stands that planets are really damned big. Frankly you could probably make a solar system detailed enough that you get more interaction and interesting stuff going on than most galaxy-spanning games just by nailing the sheer scale of this one star system alone. Many people like to assume that the earth is basically already 'at capacity' as such but I am more of the opinion that Isaac Arthur got it right:
https://youtu.be/TqKQ94DtS54?t=1185Basically for a high tech and highly industrialized civilization the earth could potentially house hundreds of billions alone without even necessarily getting particularly close to covering the surface.
There could be fairly massive and powerful civilizations (by our current standards) living on fairly minor bodies in the solar system, let alone major systems like the Jovian or Saturnian moons.
The level of complexity that such an environment could house is frankly quite spectacular and far beyond what most science fiction environments even scratch the surface of.