I don't know if there is ever just one. Purely my observation here, and as always, 100% guaranteed to be 100% wrong, but it seems to me like there is a time for all kinds. From the beginning, it seems, Alembic took on the Baskin-Robbins 31 Flavors approach to wood selection. Some combinations worked well and became popular, like that zebrawood for instance. That's an iconic 70's look, but then, so is a birdseye maple on mahogany. Some folks like the dark woods, walnut, and rosewoods, and cocobolo is prized on an a top-of-the-line Alembic now.
Me... I wonder what the least seen woods are. Peroba Rosa? Goncalo Alves? Lacewood? Tulipwood?