Productive Scale needs some Enhancements

[Micah]

How about bumping the gold modifier to 4% instead of the current 2? That would certainly increase the effect of the scale, as sloth-3 it would offset nearly 2 points of order instead of just one. Might sting enough to make it less of an auto-pick, and would help out nations that do take production, which are generally somewhat hindered due to the points they have to spend on it instead of a bless/SC.