Design Analysis: Diplomacy in Rising Tide

One of the big changes in Rising Tide was the replacement of the open ended trading between Civilizations with a much more constrained system involving a new resource called Diplomatic Capital.  Open ended trading has existed since Civilization 3.  While the trading system has changed over time (Technology Trading was replaced with Research Agreements in the move from Civilization 4 to Civilization 5) this represents a far more radical change.  Despite the new system being controversial I believe it is a significant improvement that will be carried through to future games in the Civilization franchise.