It's not a real pain or anything when it comes to gameplay, but surely if you've played a handful of games with bots and then maybe some with a friend or such, you'd know the bots change their stances and dialogues in diplomatic exchanges (Like how Isyara of the Vodyani becomes more relaxed and almost blissful when on good terms with them). Meanwhile with another player you're always on that negative-neutral appearance and dialogue even if you are in an alliance. 


Personally I'd suggest there could be a small "Set Relationship Status with [Player name] to: (And there would be a list of like, Coridal, Friendly, Angered, Afraid, etc etc) button in a corner on the diplomatic screen where you would go to and see all the other empires and start negotiations. That way you can show your friends how happy you are to purge the galaxy of the opposing force together. 


 Again, how the relations stand now don't hurt gameplay in the slightest, but the nice little asthetic touch this idea adds could be a good touch.