Layout

You've made your window quite wide. If the content is expanded to fill all that space, it would be more difficult to read because humans are better at processing narrow columns, and if you add more content columns, the UI would become cluttered and difficult to understand. If you look at any modern website, you'll see narrow content columns (and generally very few of them - Facebook's 4 columns have been quite controversial, for example). Here's how much whitespace there is in Google's search results:

Honestly, those columns all but disappear when you zoom into the page...and I don't know many people that don't have this game on a pretty substantial zoom% due to the text being so small. Filling these blanks would make zooming either ineffective or impossible, but I'd rather see a general scaling-up of the currently-present information vs. adding something else (though depending on what that "something else" is, I could be swayed)