Yep, that's it exactly for me. I end up stopping games in the 1500s now because it's so easy to get ahead due to not needing a military. Sure, I could crank up difficulty, but that just give the AI more bonuses that I have to compete with. I want the AI to respond to my military weakness and huge econ/science base, not just sit back and try and out build/out tech me with massive artificial bonuses. In short, at the same difficult at which I was playing G&K and being challenged, I'm bored to tears by 1500. No threats, no need to do much more than crank the econ/science machine and hit 'Next Turn' until I win.