I found three things which I think should be changed/fixed.
1. The "PLAY MUTLIPLAYER" button on the homepage, and the "SAVE" button in the emblem editor
(easy examples)
.
They seem hidden away with that border colour, I'd personally like them to stand out a bit more.
2. The server-name & players colour when active in the server browser, it doesn't fit the rest of the theme.
3. I find it somewhat annoying to read forum posts, because the background makes all of the text in the middle go together with brightest area of the background image.