I was thinking a more neutral darker brown kind of like
GW Scorched Brown (don't know the new equivalent, sorry).
However this works too. Ultimately it is up to your personal preference decide on what you like best mate.
At the moment the brown looks too close to the yellow in tone a darker brown would offset the yellow more. Although for me that sort of brown looks great with the beard.
What sort of base are you planning?
Bases are a great way to tie everything up or provide contrast.
Also hitting it with a wash, especialy on the metallic areas with help the overall look.
Although I do like the Green and the Gold/Yellow.
It is quite Australian by the way...