Overall i like the changes with crusade and i'm actually having a great game apart from the broken espionage and it's just killing the whole thing for me. The most you can do for security is have 10 leaders focussing on it which gives you a boost of 60% but at that rate it is still possible to lose three techs some turns. Furthermore, they start working on you when you get to unfriendly it seems and once they have started stealing your techs, they don't stop so your only option is to just kill them. Even if you make peace and improve relations, they will still keep stealing your techs and it is impossible to stop them.
I just researched a 26 turn tech and i can't do anything more to protect myself against tech stealing and it was taken and there is nothing i can do about it. I can defend my planets against enemies and culture, i can increase research & production but i am simply unwilling to accept that there is simply nothing you can do about tech stealing and just have to put up with it.
Sadly game breaking.
You can fix everything else, but not this, i don't want to give up but it's just too annoying.