Right now all the important menu entries are at the very top and the left of the screen which is the most inaccessible place for most users. Screens are still getting larger so this is a real problem.
This spacer could be of a standard (~1/4 screen height?) or user defined height and could be empty or contain design elements or information. Information could be stats about the podcasts (how many, how long, etc.), the current time and designs could be random wallpapers, pattern or the thumbnail of the currently playing podcast. Would be cool if the spacer could be shown or hidden like the other menu elements.
I think as a start a blank spacer would be enough to achieve better usability and could be implemented fairly easily. Any bells and whistles could be added later.