'starbases in foreign space sure would make nice bargaining chips...' has been in the forum since beta 2. It would be nice if they could be traded like ships or planets.

Someone mentioned earlier that we should have a few turn's notice about what the next vote will be. I wholehartedly agree! I'm playing a game right now where a vote came up to give a race a %50 influence bonus. Had I had an opportunity to look at the map, consider my trade routes, check my diplomatic status, etc, I would have had the chance to vote for one of my allies. I currently don't own a majority vote in the senate, so voting for myself wouldn't do much good. Since I had to make an uninformed decision and just vote for myself, my main enemy in the game just got the vote. This may have cost me the game.

We really should have at least the ability to look at our other screens before inputting a vote. A 1-turn notice of the subject of the next vote would be very condusive to diplomacy.

Don't know if this has been suggested before, but how about "wimpy allies"? For example, you're allied with the Torians and decide to attack the Dregins. The Torian diplomacy screen pops up and the ambassador says "Holy Shinola, what are you doing? We've only just gotten Battle Axes and you want to attack the Dregins? We can't support you and remain in this alliance unless you give us Battleship technology." Or perhaps "We demand that you give the UP inspectors more time! We will not be a part of any unilateral action!"
This would seem to me to be appropriate only when your alliance is attacking, not when it's attacked, and when the alliance partner is weak, and/or if the alliance has not been kept on good terms by continuing trade, tech trades, voting alliances in the UP as suggested by others, etc.