#1 Arms technology should only be traded to allies or friendly players regardless of the price. Make players or the ai research their own weapons unless they are in an alliance together or at war with a common enemy. This makes sense, even friendly nations are very cautious about trading nuclear weapons technology.

#2 Improved Interface, a right click option on ships to get info and to allow more options such as adding the ship # to a trade window or directly giving the ship to another race. As a game play I often send fleets of ships to assist another race, without getting directly involved. Instead of having to look and remember Battlecruiser 898901 and 822234 when going to the trade screen it would be nice to just right click on the ship and give it to a race.

Improved Fleet creation managment. It's also impossible to get info on a fleet when its a stacked set of units... I like to see what weapons a fleet has before engaging.