Just two suggestions really, Being able to observe a friend when they are in-game from the friends list instead of it being a tiny little icon in the top right of your friends profile page-- Unless you already can, and all my friends were just in… unobservable games?
Second, is being able to access your Mastery from the Esc menu. I got into game and I blanked on what my mastery bit was-- had to alt-tab, shift my camera slightly, open up chrome, google the mastery of the civ and click a link, and look, Alt-tab back in. It would be nice if it were to show the mastery at the top of the screen in the ESC menu or something.