While the Wood theme is out of commission for the time being, I have reverted to using R4 themes. Unfortunately, the R4 themes that come with TWiLightMenu do not really fit stylistically.
I spent some time today and ginned up a DS skin (inspired by an old skin by puszcza).
(Left icon brings you to your SD Card. Middle icon launches Slot-1. Right icon launches GBARunner2.)
If you want to use these, just save the attached BMPs to your 3DS microSD card in a new folder in _nds\TWiLightMenu\r4menu\themes.