Not to be a contrarian, but I think they are doing everything possible to make C5 a combat game.
Per my interpretation of Schafer's E3 interview, he said (more or less) that City States are designed to mix it up. Left to themselves, two civs might find a way to live in peace. So, City States were added into the mix. By design a City State will tend to like one of its neighbors (who it will ally with) and hate the other (who it will force its ally to attack). Walla, instant war.
In Civ 4, a civ could found Buddhism, send out a few Missionaries, convert their neighbors, and force a PAX-Religious. This was presented as a negative thing in the interview. And so, in an effort to allow civs to act more "rationally" (which in a war game, means going to war), religion was removed.
Further, one of the examples of play shown was of a nuclear attack launched against a civ who was about to win a Space Race victory. The nuclear attack forestalled this victory. Such a turn of events clearly places a warmonger strategy above either a builder (Space Race) or cultural (Utopia Project) strategy.
Also, consider that Panzer General has been heralded as a driving inspiration for C5. Not Settlers of Catan, not some wishy-washy do-gooder liberal game, but a hard and fast old school war game is denoted as a major inspiration.
Thus, I expect C5 to be a fairly straightforward war game.
War will be inevitable.
The march of Civilization will be measured by one's ability to engage in war.
So, what does this mean for diplomacy?
For one, a fog of uncertainty surrounding diplomacy will make it harder to tweak the peace. Sure, it makes the interface feel more organic, but more importantly, juggling the needs of competing factions becomes all but impossible if one doesn't know the numbers.
Secondly, not only am I expecting war, I'm expecting a lot of it. Me and Monty will no doubt fight over City State A (Shanghi?), while Louis and Elizabeth fight their own little war brought to a head by the Medici in City State B (Tuscany?).
From there, my oracular powers grow a bit dimmer.
But I am hoping that by mid game, the civ on civ hostilities will morph into World Wars. I mean, those are more fun right?
And then in the late game, it'll be every civ for themselves as alliances switch quickly and any who pull ahead and look like they might win are mercilessly attacked by all who remain. After all, who launched all those nuclear weapons in the demonstration? My guess: everyone who had them.
Which is to say, I'm expecting the AI to act more like a Machiavellian Prince, more like a war gamer, more like someone or something that actually wanted to win the game at any price.
"So, it's all fine and dandy that you have a +1 bonus for open borders. +2 for the resources you've given us, +3 for all the years of peace, and yeah, even the +6 for joining our war against Monty, we're not forgetting that. But you see, we've looked at the numbers, and well, there's just no way we're going to win this here game unless we start capturing some cities, and sad to say it, but yours are the first on our list.
Prepare for war!
Gandhi atttacks."
All that said, I hope the AI has to play by the same rules I do, but have no faith that they will.
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