I'm quite sure that players will be annoyed if the AI uses espionage more actively. I may later make more changes to make the AI, in some circumstances at least, use espionage more vigorously. At any rate, making it prefer poisoned cities for unhappiness mission and vice versa is quite possible.
Kalimakhus, I quite understand your concerns. However, I am keeping the filename the same all the time on purpose. You can look into each zip file to see its modified date if you need that.
And no future estimates are possible, largely. If they are, I say so - like now I said that the colony bug will be fixed for the next update.