When it comes to Luxury Monopolies, they're just too easy to get. I just don't like the fact that 6 Copper start all near one another and it takes me only two cities to acquire the Monopoly - in the real world, Copper is deposited in chunks, yes - but many chunks, not just one.
I agree, although I think this is done for game balance. CBP IMO is already too biased toward "wide" play (most likely a side effect of vanilla bias against "wide"). If recourses were spaced more realistically, it would favor "wide" even more.
The thing is that I usually CAN do without Iron/Horses most of the time, and I'd argue that precisely for that reason, your monopoly because worth less, and not more. I will simply give you nothing and laugh at you while you have all these extra resources sitting around that you can't use. It doesn't matter, anyways, because the AIs don't think in your terms and aren't willing to pay more for your resources even if you're the only one who has them - though they will pay something.
Ah, but I could sell them to everyone except YOU, and thus leave you with a severe competitive disadvantage. I also noticed how you singled out two specific resources, implying that if the recourse were say... oil or uranium, you'd be doomed.
I'm not talking about Iron or City Trading, though, I'm just talking about one-for-one Luxuries. I have a hard time thinking of any reason why even the Civs who hate each other more than anything else in the world couldn't agree to a one-to-one Luxury trade.
Civ A has just about every "green text" there is with you.
Civ B doesn't care much about you one way or the other.
Civ C is your mortal enemy. They are just a wall of red text.
You need a luxury and all three civs have an extra copy of it, while you have a copy of a recourse that none of them have. If they all charge the same price, you're going to trade with Civ A. Civ A is less likely to declare war and make you lose the luxury you need than the others, and the extra happiness is less likely yo be used against you. All other things being equal, you'd rather deal with your allies.
Now, same scenario, except Civ A and Civ B don't have the luxury you need and Civ C has 3 copies. Civ C is your only option. They aren't going to be fair, because they have other possible customers that are far less likely to backstab them. Unless they are also in desperate need of the luxury you have and they also can't get it elsewhere, they should just sell to Civ B (and possibly Civ A if their assumed DoF with you doesn't spoil their relations). If they do sell to you, it only makes sense that they'd want to charge extra to cover the risk.
However, if Civ C approaches YOU for a trade, then it makes sense that the tables should be turned - they should expect to pay YOU more, since you're the one taking on the extra risk when you could sell (assuming the trade isn't a DoF offer). The AI currently does not do this - "Hostile" Civs will keep offering you "Accept Embassy" for a luxury.
However, you are completely correct in a specific scenario - monopoly selling to monopsony. If Civ A and Civ B have exactly 1 of the resource you need and Civ C has 2, then (assuming Civ A and B are unwilling to sell their lone resource) Civ C is your only option... but you're their only option as well, as they have no other civs to sell to. You're both taking equal risks and you both have no other options. Logic would dictate an even trade regardless of your feelings about each other (and no, the AI doesn't take this into account either).
I have never, ever, seen them do this. I'm usually laughing throughout the whole game as I happily give Open Borders away to share all my Tourism. My more sincere concern is that if one wanted to stop a Culture Victory most of the time, it's too easy instead of too hard, thru a simple war declaration.
Really? Every single time for me, high culture civs will start refusing open borders the moment they realize I'm going for cultural victory, and will continue to do so (even if we have a DoF and defensive pact in place) until my tourism overtakes their culture.
But I agree about the war declaration. In my most recent game, the highest culture AI simply refused to make peace with me thus denying me the trade route bonus or a diploma. Granted, it was because of a bug (the AI would keep offering me peace yet refuse their own offer) but what's stopping me from doing that trick to an AI trying to win by culture? In the end, I did win, but only by eliminating the offending civ, which really isn't a cultural thing to do.
I think this is a bad argument. I've won games (not necessarily Civ) while losing badly because I fought tooth nail and claw to prevent anyone from winning, only to take advantage of a situation when it presented itself and claim victory (e.g. finishing off a specific player's Capital when he owns everybody else's). I understand that Human players can become demoralized, but there's no reason that an AI should be so.
This wasn't actually about being demoralized. If an AI trying to win by cultural is "Dominant" over you (ie - the rank past "Influential") there is little point in denying them open borders, because you can't really make a cultural comeback. What you CAN do is use the extra GPT from accepting open borders and try to win another victory condition before they overtake the other high culture civs. The AI actually DO this already.
Still dangerous, as other players can use Espionage to steal it. Not as swift as trading, true, but if you're in the lead by a fair margin, why take the risk?
Ehh... usually the AI never plants spies on me if I'm losing, so it likely treats other AIs the same way. If they're going to steal the tech in that scenario, they'll steal it from me, not the loosing civ I sold it to.