I don't mean that we should copy the real life Sol System, just those parts that greatly affect life conditions and civilisations. This would include:

• the type of star
  
• the stability of Pacifica's orbit around it (no massive planet near the star)
  
• having the same orbital properties as the RL Earth
  
• having no habitable planet except Pacifica
  
• having "vacuum cleaning" planets (gas giants)
  
• having no massive planets near Pacifica