Experimenting with wood

I have recently purchased a pyrography kit and have been experimenting with drawing onto wood. I think this works well the nature of my drawings although MDF doesn't quite give the effect I would like. I am currently testing out different types of wood as I would like to include the grain into my work.
The 'thing' over his eye is one of the natural objects that I have collected on my travels. (I'm not quite sure what to call them so if anyone knows please let me know)