@Avengeil I was hoping someone more knowledgeable in gimp would give you advice, I'm not really certain myself.
@ ajb47 Sorry I missed your question. Aside form finding elements others have posted, you could try to make a more fern edged brush and see if that helps. My method really only works well for fuzzy brush and scrub. You look like you have something good going with the texture you've chosen at very least, you could even choose that texture as as the "texture" under the bevel/emboss option and make those leaves look more shaded.
@ Moonblade You're most welcome, that looks like it will add a lot to your game experience!
Great to see people using the tutorial, love seeing the results.