I really need to bring up the issue I've been experiencing on these procedural maps, particularly in underground areas.
-In one game, had 8 AI players and couldn't find one until the very end of the game. Turns out the AI was placed in the corner of the underground with not passages to the surface unless it excavated (which it never did)
-Current game am experiencing a serious issue with the AI placing a city RIGHT NEXT to a passage that was also cornered....Meaning only one army at a time can go down and of course will be slaughtered as it will get overwhelemed by a group of three armies. Ended up having to re-route to avoid this but it bought the AI enough time to produce more armies and drag things out A LOT....This screw up has easily added 20 turns or more to eliminating this player. Yikes!
-Several more instances of extremely poor placement of cities next to passageways underground. Not as bad as the example above but it does create issues.
Personally, I don't think Free cities should be within 2 provinces of one containing a passageway, and no player (AI or human) should be allowed to build a city or outpost within 2 provinces of one. Some of the exploitation I'm seeing is pretty abusive.