too bad you cant build espionage, like wealth, research and culture (perhaps in a 1 to 8 ratio?). I typically have 0%, but change to 10% as my civ have the excess gold pouring out from banks while keeping research at 60-70%.
I played 3 games in BTS so far, and there was only 1(!!!) time when an opponent made a successful spy action against me.
if you built Scotland Yard with the second spy it would have been even betterBeen experimenting in my current game with espionage seeing as I got two great spies from the Great Wall. With them both settled in my capital I have been able to see everyone's research ever since, which is great for having the slider at 0%.