What makes a bass playable and sound good? Since there are many components and everyone will have their own opinion and more than likely probably a combination of a few things. For the sake of bringing a bass down to it's common denominators, it's best to narrow the choices to 3 items.
IMHO, the Magic is in the neck. If the neck is bad, then the other components will not matter because of the lack of playability.
Also, most manufacturers add the serial number to the neck and not the body.
Your left, and right, hand fingering probably have more to do with tone, than anything.