Yeah, ash makes a good back wood coz of cost & it also blends well sonically, with most woods.
A top on a BO is 3/8" while the top on a NT is a full 1" coz of the contoured body.
The sonic stew sure is a complex thing, & that's without even taking into account the way the different woods are cut.
WW neck laminates are cut & glued with the grains running at different angles. I forget which laminates run in which directions, but I thing this also has a big affect on tone, sustain, attack, etc. The neck tension alone has a major influence on sustain. A neck with zero tension, like that Henman Bevilaqua bass, has no neck tension, & has possibly the longest sustain of any stringed instrument. Our WW necks are under immense tension, & we all know how much bloody sustain we have, especially when we've fitted new strings.
I wish I knew more about luthiery & whatnot. It really boggles the mind.