Culture 1)I quite like the idea and many parts of the implementation, but I think the way in which culture overlaps or is broken needs to be changed.

I think it would be much better integrated if culture came from all the "logistic" buildings. Why not just create two classes of building? military and cultural(economic? civilian?) rather than tactical and logistic. put all the offense/defense/building warships into military (maybe except for capitol shipyards, which could give a civilian bonus since they are the crowning achievements of a militaristic society) and develop the trade arm (and techs) of the game further. you could amass an empire by paying others using bounties to take out pirates and enemies who mess with your trade ships.