Leoreth, take a look at this abuse of the new spy/espionage system.
It takes one turn for my spy to reach Lisbon. For next to nothing he can perform the Spread Culture misson. Most likely he'll succeed and return to the nearest city. With the avoid detection promotion it'll be impossible for him to fail soon.
Also notice the spy points required for the next Great Spy is 24.
Then I just mass produce spies and have them do the same. Soon my 1st GS is born.
Notice the spy points requirement only goes up to 36.
Then only 3 turns later, my 2nd GS is born. And I only need 48 more spy points for the next GS.
I didn't invent this, but this is what game abusers do. I'm just trying a Spain game and this is naturally the way to play, obviously it quickly gets boring. I know it's common to get a ~100 exp super spy a while into the game and that doesn't sound right.
And another thing, right now for most of the cases, the best strat for Euro civs is to rush each other on spawn. It's best because it's possible. To(partly) fix that, I suggest giving the human player the minimum of units(like 3 archers for 3 cities, not even longbows) on spawn, and with little to no starting gold(so no mercenaries). Especially no knights for civs like human Spain. Holy Rome can have some units because they need to capture Roma to win their UHV.