I did give up on wood filaments long ago, exactly a year ago, mainly because changing nozzles on umo hurts the aluminium block quite fast. Also because I didn't found enough cooling for the speed I wanted to use.
This it's printed with my um2fancap for umo+ (doesn't work for um2 frame) with a 0.6 nozzle at 70mm/s 0.3 layers, and retracts on (but optimized on speed and amount so the weak wood filament doesn't break).
I'm quite happy with the result specially since it takes just 1h and 10mins to print.
The flower it's printed on 2 parts, glued, and then glued with epoxy to the cactus.