I have an idea for the base skin and main menu: Extending the %cs functionality and getting rid the main menu displaying the top row (Rockbox/Settings/Playlist/...). That would open up possibilities for themers and could even save screen space (by using multifont or images) Would that be feasible?
Turning off the top row would have to be optional to keep compatibility with older themes, of course
With the %cs tag being able to return the current menu screen as text/bitmap in a separate window, you could allow for a bunch of new theme layouts and save some vertical screen space as well (by displaying %cs left or right of the menu).
I hope I don't sound too confusing, excuse my bad english