SC2Mapster

Here's a suggestion that I believe to be simple in concept, would take a reasonable amount of time and effort to implement, and would be well worth it:

Naming component, ship hull, ship design and building versions, as well as naming planets.

Being able to give names to the various components and facilities, but more importantly ship designs, that you come up with during a game would be very helpful in managing your empire when you inevitably end up with six different types of everything and can't remember which one is useful for which situation.

Also, when I say "renaming planets", it might be a simple "Rename" button on the Empire Overview window that would change "ID: [planetID]" to whatever the player enters in a popup box when the rename button is clicked. This would also help tremendously with managing one's empire, since you'd be able to name planets in a meaningful way, such as "Sector 1 Metal Planet" for example, and then you'd know that this planet supplies metal for the "Sector 1" group of planets. This is just one example, of course - the point is in the freedom and tools that it gives players.

Also, I strongly suggest you rename "buildings" to "facilities" - in 4X games, the term "Planetary Facility" is much more common and easy to recognize than "buildings" or, really, any other equivalent terminology. I know that "building" is probably a more accurate translation from other languages, but "facilities" is more appropriate and feels more comfortable to english-speaking people experienced with 4X games.