Well think about it like this...Diplomacy victory with the DLC is one of the most plausible and optimal victory types, whereas in Vanilla Diplomacy Victory type was probably the least-rational victory to pursue. You had to reach the end of the tech tree and then build United Nations - with that much science you could just go to space. Therefore in Vanilla, the Greek UA did not directly help them achieve victory but purely provided them with economic benefits. Now with the DLC their UA actually helps them directly achieve a plausible victory type.
Also on the DLC, gold may bring less influence but I feel that there are a lot more quests now, so you can still gain just as much influence, just in new ways.
Also on the DLC, gold may bring less influence but I feel that there are a lot more quests now, so you can still gain just as much influence, just in new ways.