|Bark reference pic of which I might try to emulate.|
Many of the GW Wood Elves -of which the Treeman will be a part of- use these weird leather half-masks, which had some dissenting opinions at the time. I might have opted to use them less in my miniatures. After all this time I feel the masks are okay.
Now I had an idea connecting all these three. A Treeman face with half-mask made out of bark, with a hole for an eye which would be sculpted as above. Maybe a Treeman Ancient (the one who can do magic), so he'd look more mystical than the regular Treeman who's limited to punching fools.