Making new Gas Giants might seam like a unfamilar idea.Usually it would be like creating a new Earth that is about 10,000 km across but it is not. Gas giants make great systems of their own.Jupiter has 4 giant moons.Saturn has 1 Giant moon and 7 other medium size moons.It is likely that gas giants are as easy to make as any terrestal.This process do not have to take a billion years to make.This process can be done in thousands of years.