There's still a lot of work to be done, but I thought I'd update you all on my progress with the diplomacy screen. The interface placements are not final, I'm still tweaking and seeing what looks good. The relationship bar is fully working, it shows your current relationship with that empire, along with a label for it.
The plan is to have each item in the list on left be a button, and when you click on one item, it brings up that empire and list of actions you can do with them on right. When you've selected an action, it saves your selection, and is sent to them the next turn.
If you've received a message, you can open it and choose to accept or not the message (trade, etc).
I'm thinking of adding icons to represent different statuses, such as War, Allied, Non-Aggression, Trade, etc somewhere on each contact. The diplomacy framework is done, just need to set up the interface in a clean and clear way.
Here's the preview of the diplomacy screen. It is subject to change, but thought you'd like to see what I have so far:
Yes, that is the human art that my artist provided. My "Zero People" race art totally stinks compared to human art!