I suppose anything would do. I think my vote would go to sort of an artistic visualization of a level, like for example how you did the header on your website. The title perhaps could be composed of those gray blocks.
Also, I would not align the menu like that, unless there is a good reason for it of course, such as an image that is placed next to it and the menu is aligned to follow a pattern to match the image. Centered alignment is usually the best way to go.