I've only played a few games, but it seems to me that diplomacy is completely useless. First, we can't initiate anything. This means we must react, so there is no strategy at all. I've lost two games in a row (4v4 FFA 3 Normal AI) to simply getting ganked by two empires at once who were on both borders.

We need the ability to manipulate the other empires into working with us so if we see Empire A on our left border, and Empire B on our right border, we can work something out with at least one of them so both aren't hostile. However now, they will both often want you to attack Empire C, which you can't even get to - and when you can't, they just hate you and come attack you.

Anyway, I love the game, but it's not much fun getting ganked on multiple sides and not being able to do anything about it.