It would be nice if when you right-click on a tech, it would show you where it is in the tech tree (what's before, behind, etc., with links, plus a link to diagram, etc., as in civ 4.
The one place I constantly want to know where a tech falls on the tree is when trying to trade tech with AIs. I want to give them a tech that is next in line for them, not one that is two or three steps ahead! Its a waste to give them the better techs, as then the old ones can't be traded later (AIs don't value letter tech even if they don't have it yet).
Similarly, trade screen should give me pop-up info on the monopoly items as well - its sometimes hard to remember what The Restaurant at the end of the galaxy realy does, or the Alien Spices, or whatever, and hence whether it is a acceptable trade item or if I should not let it into the hands of the AI i'm trading with...