I would have to recommend Star ruler, you can make custom ships which that can be bigger then the suns and you can add unlimited amounts of planets and ships (As long as your computer can handle it and I wouldn't recommend using more then 500 planets unless you are using Sandy bridge Extreme, and I would also have to suggest that you set a limit on many ships you can build since otherwise you should expect at least 1k turrets on every planet that the enemy controls and then your pc will pretty much crash if you are playing with over 500 planets)
It's a 4x game (Large scale, real-time grand strategy set in space)
http://starruler.blind-mind.com/
It's a 4x game (Large scale, real-time grand strategy set in space)
http://starruler.blind-mind.com/