So the serious disadvantage with a "diplomatic ability" in multiplayer is that human players aren't likely to do what you tell them just because you have an arbitrarily high diplomatic skill. In fact, diplomatic ability is only particularly useful if you have powerful AI opponents that you can bargain with (a tall order in a multiplayer game). Considering diplomacy is its own tech tree, throwing diplomacy-heavy kingdoms a bone would be a good idea.

Enter Diplomatic Pressure.

Diplomatic Pressure is essentially diplomatic arm-twisting. On the diplomatic table, you can add "pressure" to the deal, which adds a unspecified negative consequence to rejecting the deal. Essentially, "pressure" represents a general perception that the deal is reasonable and to reject it would be unreasonable.

The consequences of rejecting a pressured deal can be specific or it can be random, sudden or gradual, severe or inconsequential, depending on what's better for balance. Here are a few ideas:

• Sudden dips in relationships between the player's faction and other AI factions
• An increase in negative random events.
• Fewer quests offered.
• A temporary drop in diplomatic ability
• A temporary sudden gain the diplomatic ability of the pressuring nation
• A loss in efficiency of treaties and trade routes with other nations.

But Will, can't you use diplomatic pressure as essentially a hostile act? Yes, and people should. Making ridiculous deals and then putting pressure on them could be a strategy in and of itself. Obviously, you can't have people doing this all the time, you'd need to balance it, but this kind of assholishness I think is healthy in a game. In particular if you've picked the path of diplomacy, in which case you probably need all the help you can get. Of course, overusing this is a double edged sword, as you're bound to piss people off and hurt your relations. You'd better have powerful allies.