[Aussie Gamer]

I think that a fatser rate of production on Space based yards is a good idea, as if you think about it you can gain access to the entire ship. This would allow for a faster construction of ships.

See Massive Ship Yards for my ideas on that subject.

I don't think that slowing done the planet based ones though is a good idea though, at the start of the game you only get yards 1, not very fast. With this level of tech at the start planets should build faster. Think about now in the USA. They build on the planet. But in the future mankind would most likely build massive ships off-planet, higher tech!!