Gombeira is new to me too but I've had good luck following my luthier's recommendations when it comes to wood.
I wanted a really rich, ++ overtone sound and this was Jeremy's suggestion. He said -
Gombeira is a really special wood and in my opinion is in a class with very few other woods. It has a much lower level of damping and a much higher velocity of sound than pretty much anything I’ve ever tested. From a sheer material properties perspective it makes wenge look like cardboard and wenge is no slouch of a wood. It’s incredibly rare and the trees don’t get very big. I had the chance opportunity to purchase a couple of narrow boards several years ago and I haven’t been able to find any since. The back on that previous Gombeira instrument is multi-piece (I think it was five actually).
Note that he was talking about Wenge, which was my original choice.
Here's a pic of the aforementioned previous Gombeira instrument of his:
eu5g09clcznj0yaiqghq.wdp by
Tristan Koehler, on Flickr
It looks great too!