More UI Feedback
I would like the Citadel level to be displayed in brackets next to its name when you float your cursor over it so that when you hear it level (via announcer) you know what upgrades were unlocked by memory. I would also like the ability to have UI popups for things I put in place. For instance after locking a flag have a little UI counter that counts down to let me know when it expires.
Simple feedback to the users about whats going on makes the game better because you don't have to constantly babysit unimportant things.